Universitätspublikationen
Refine
Year of publication
Document Type
- Article (1546)
- Preprint (967)
- Doctoral Thesis (379)
- Conference Proceeding (227)
- Bachelor Thesis (74)
- Master's Thesis (61)
- Contribution to a Periodical (46)
- Book (29)
- Part of Periodical (27)
- Diploma Thesis (22)
Keywords
- Heavy Ion Experiments (20)
- BESIII (17)
- LHC (15)
- Hadron-Hadron Scattering (11)
- Hadron-Hadron scattering (experiments) (11)
- e +-e − Experiments (11)
- Heavy-ion collisions (10)
- Relativistic heavy-ion collisions (10)
- ALICE (9)
- Branching fraction (9)
- Heavy-ion collision (8)
- QCD (8)
- Black holes (7)
- Equation of state (7)
- Lattice QCD (7)
- Particle and Resonance Production (7)
- QCD phase diagram (7)
- HADES (6)
- Ionenstrahl (6)
- Quark-Gluon Plasma (6)
- Quarkonium (6)
- equation of state (6)
- focused electron beam induced deposition (6)
- Charmonium (5)
- Collective Flow (5)
- Electronic properties and materials (5)
- Hadronic decays (5)
- Jets (5)
- Magnetic properties and materials (5)
- Quantum chromodynamics (5)
- RHIC (5)
- Strahldynamik (5)
- Teilchenbeschleuniger (5)
- Toroidales Magnetfeld (5)
- density functional theory (5)
- heavy-ion collisions (5)
- radiation-induced nanostructures (5)
- ALICE experiment (4)
- Atomic and molecular interactions with photons (4)
- Beschleunigerphysik (4)
- Branching fractions (4)
- CBM (4)
- Charm Physics (4)
- Charm physics (4)
- Charmed mesons (4)
- Cryoelectron microscopy (4)
- Dyson–Schwinger equations (4)
- Electroweak interaction (4)
- FAIR (4)
- FEBID (4)
- Fluctuations (4)
- Gross-Neveu model (4)
- Heavy Ion Collisions (4)
- Heavy Ions (4)
- Lepton colliders (4)
- Monte-Carlo-Simulation (4)
- Nuclear reactions (4)
- Particle and resonance production (4)
- Phase transitions and critical phenomena (4)
- Polarization (4)
- QCD equation of state (4)
- Quark-gluon plasma (4)
- Quasi-free scattering (4)
- RFQ (4)
- Spectroscopy (4)
- inhomogeneous phases (4)
- mean-field (4)
- phase diagram (4)
- phase transition (4)
- quark-gluon plasma (4)
- stability analysis (4)
- synaptic plasticity (4)
- Beschleuniger (3)
- Compact stars (3)
- Cross section (3)
- D-wave (3)
- Emittanz (3)
- Energy system design (3)
- Exotics (3)
- Experimental nuclear physics (3)
- Experimental particle physics (3)
- Extra dimensions (3)
- FOS: Physical sciences (3)
- Fisher information (3)
- Flow (3)
- Gabor lens (3)
- General relativity (3)
- Guided waves (3)
- HBT (3)
- Heavy ion collisions (3)
- Hebbian learning (3)
- I-wave (3)
- Initial state radiation (3)
- Inverse kinematics (3)
- Jets and Jet Substructure (3)
- Magnetic field (3)
- Neutron star (3)
- Neutron stars (3)
- Nonperturbative methods (3)
- Nuclear Physics (3)
- Particle decays (3)
- Phase Diagram of QCD (3)
- Physics (3)
- Proteins (3)
- Proton (3)
- Quantum field theory (3)
- Quantum gravity (3)
- Quark-Gluon-Plasma (3)
- Quark–gluon plasma (3)
- Radiative capture (3)
- Relativistic kinetic theory (3)
- Schwerionenphysik (3)
- Spectroscopic factors (3)
- Speicherring (3)
- Strangeness (3)
- Superconducting properties and materials (3)
- beam dynamics (3)
- brain stimulation (3)
- compartmental neuron model (3)
- computational model (3)
- correlated electrons (3)
- cosmological constant (3)
- dark energy (3)
- deep learning (3)
- detector (3)
- e+-e− Experiments (3)
- elliptic flow (3)
- game theory (3)
- gravitational waves (3)
- heavy ion collisions (3)
- heavy ions (3)
- hyperons (3)
- lattice QCD (3)
- moat regime (3)
- motor cortex (3)
- multi-scale modeling (3)
- neutron stars (3)
- objective functions (3)
- pp collisions (3)
- quantum chromodynamics (3)
- relativistic heavy-ion collisions (3)
- strangeness (3)
- terahertz (3)
- transcranial magnetic stimulation (3)
- transport theory (3)
- two-point function (3)
- wave-function renormalization (3)
- α-RuCl3 (3)
- 3D printing (2)
- Accelerators & Beams (2)
- Activation (2)
- AdS-CFT Correspondence (2)
- Atomic and Molecular Physics (2)
- Atomic, Molecular & Optical (2)
- Beauty production (2)
- Bethe–Salpeter equation (2)
- Bhabha (2)
- Biochemistry (2)
- Biophysics (2)
- Biophysics and structural biology (2)
- Black hole (2)
- Boltzmann equation (2)
- CBM Experiment (2)
- CBM experiment (2)
- Casimir effect (2)
- Chemical physics (2)
- Chiral phase transition (2)
- Chiral symmetry (2)
- Chiral symmetry restoration (2)
- Color superconductivity (2)
- Complex networks (2)
- Computersimulation (2)
- Conformal Field Theory (2)
- Conserved charge fluctuations (2)
- Control System (2)
- Cryo-electron microscopy (2)
- Datenanalyse (2)
- Detector (2)
- Diffusion (2)
- Dileptonen (2)
- Dissertation (2)
- Doku Mittelstufe (2)
- Dynamical chiral symmetry breaking (2)
- EPICS (2)
- Electromagnetic probes (2)
- Electronic structure of atoms and molecules (2)
- Electroweak Interaction (2)
- Elliptic flow (2)
- Event-by-event fluctuations (2)
- FRANZ (2)
- FRANZ-Projekt (2)
- Finite temperature field theory (2)
- Functional Renormalization Group (2)
- Functional renormalization group (2)
- GSI (2)
- Gabor-Linse (2)
- Gammaspektroskopie (2)
- Gauge-gravity correspondence (2)
- Gravitational waves (2)
- Hadron (2)
- Hadron-hadron interactions (2)
- Hadronic cross section (2)
- Heavy Ion Phenomenology (2)
- Heavy Quark Production (2)
- Heavy baryons (2)
- Heavy flavor (2)
- Heavy-flavour production (2)
- Heavy-ion (2)
- Heavy-ion Collisions (2)
- Hubbard model (2)
- Hybrid mesons (2)
- Hypernuclei (2)
- Hyperons (2)
- Injektionssystem (2)
- Ionenbeschleuniger (2)
- Kaons (2)
- Kernmaterie (2)
- Ladder-RFQ (2)
- Large-scale integration of renewable power generation (2)
- Laser-produced plasmas (2)
- Lattice Quantum Field Theory (2)
- Lattice field theory (2)
- Learning (2)
- Lepton-Nucleon Scattering (experiments) (2)
- Leptonic, semileptonic & radiative decays (2)
- MAPS (2)
- Minimal length (2)
- Molekulardynamik (2)
- Monte Carlo simulations (2)
- Muon anomaly (2)
- NA61/SHINE (2)
- Nanoscale materials (2)
- Neuronales Netz (2)
- Neutron Star (2)
- Nuclear astrophysics (2)
- Nuclear matter (2)
- Nuclear modification factor (2)
- Nuclear resonance fluorescence (2)
- Nucleon induced nuclear reactions (2)
- Nucleus–nucleus collisions (2)
- Nukleosynthese (2)
- Numerical Relativity (2)
- PELDOR/DEER spectroscopy (2)
- Particle Accelerator (2)
- Particle Correlations and Fluctuations (2)
- Particle correlations and fluctuations (2)
- Pb–Pb collisions (2)
- Phase transitions (2)
- Physik (2)
- Pion form factor (2)
- Plasma Physics (2)
- Plasma-based accelerators (2)
- Protonenstrahl (2)
- QCD Phenomenology (2)
- QCD phase transition (2)
- QGP (2)
- Quantenchromodynamik (2)
- Quark deconfinement (2)
- Radio Frequenz Quadrupol (2)
- Rapid rotation (2)
- Research article (2)
- SARS-CoV-2 (2)
- Shear viscosity (2)
- Shell model (2)
- Simulation (2)
- Single electrons (2)
- Single-particle states (2)
- Spectral functions (2)
- Spurselektion (2)
- Strahlprofil (2)
- Strahltransport (2)
- Strong interaction (2)
- Synaptic plasticity (2)
- Synchrotron (2)
- TeraFET (2)
- Transport properties (2)
- Two-dimensional materials (2)
- Ultra-relativistic heavy ion collisions (2)
- Vertex Detector (2)
- Zustandsgleichung (2)
- additive manufacturing (2)
- anisotropic azimuthal correlation (2)
- artificial intelligence (2)
- asymptotic giant branch stars (2)
- atomic force microscopy (2)
- binary neutron star merger (2)
- binary neutron star mergers (2)
- black holes (2)
- bulk viscosity (2)
- chemically peculiar stars (2)
- chiral symmetry (2)
- chiral symmetry restoration (2)
- circuit analysis (2)
- circumstellar dust (2)
- composite structures (2)
- conformational dynamics (2)
- correlation functions (2)
- correlations (2)
- dileptons (2)
- directed flow (2)
- disorder (2)
- electron beam induced deposition (2)
- electronic band structure (2)
- electronic transport (2)
- energy system design (2)
- energy transduction (2)
- generating functionals (2)
- global jets (2)
- granular metals (2)
- gravitational wave (2)
- hadron gas (2)
- heavy ion physics (2)
- helical magnetic fields (2)
- heterostructures (2)
- high energy physics (2)
- homeostatic adaption (2)
- hot spots (2)
- hydrodynamics (2)
- in-Medium Modifikation (2)
- inflation (2)
- initial state (2)
- injection (2)
- kink-like instability (2)
- lattice (2)
- magnetic fields (2)
- magnetic frustration (2)
- mathematical and relativistic aspects of cosmology (2)
- molecular dynamics (2)
- nanofabrication (2)
- nonlinear dynamical systems (2)
- nucleosynthesis (2)
- organic charge-transfer salts (2)
- oscillators (2)
- p-Kerne (2)
- p-n junction (2)
- particle physics (2)
- particle-in-cell simulations (2)
- phase noise (2)
- photoelectron spectroscopy (2)
- power transmission (2)
- quadratic-linear gravity (2)
- quantum gravity (2)
- quantum mechanics (2)
- quark gluon plasma (2)
- recollimation shocks (2)
- relativistic hydrodynamics (2)
- relativistic jets (2)
- reservoir computing (2)
- resonances (2)
- s-Prozess (2)
- s-process (2)
- scanning tunneling microscopy (2)
- simulation (2)
- statistical operator (2)
- stellar abundances (2)
- storage rings (2)
- string fragmentation (2)
- structural health monitoring (2)
- system analysis and design (2)
- thin films (2)
- toroidal magnetic field (2)
- track selection (2)
- transition-metal oxides (2)
- transport coefficients (2)
- vector mesons (2)
- zero-energy universe (2)
- (Anti-)(Hyper-)Nuclei (1)
- (F)EBID (1)
- (n (1)
- 1/c 2 electronic Hamiltonian (1)
- 124Sn (1)
- 140Ce (1)
- 1st order liquid–gas phase transition (1)
- 2 + 1-dimensional field theories (1)
- 2D materials (1)
- 2D vdW magnets (1)
- 3-atomic-heteronuclear molecule (1)
- 325 MHz (1)
- 4-ROD RFQ (1)
- 900 GeV (1)
- AGB star (1)
- AGN host galaxies (1)
- AGN jets (1)
- ALICE detector (1)
- ALICE upgrade (1)
- ALICE, Teilchendetektor (1)
- AM-PM noise conversion (1)
- ATR-FTIR (1)
- Ab initio calculations (1)
- Abbremsen (1)
- Absolute branching fraction (1)
- Absolutkonfiguration (1)
- Absorptionsspektroskopie (1)
- Accelerator (1)
- Accelerator Physics (1)
- Accelerators & storage rings (1)
- Accreting black holes (1)
- Action potentials (1)
- Activation experiment (1)
- Actuators (1)
- Ageing (1)
- Aktivierungsmethode (1)
- Akustik (1)
- Alignment parameter (1)
- Alignmentparameter (1)
- Alternating Phase Focusing (1)
- Analysis (1)
- Anderson Impurity model (1)
- Anderson-Modell (1)
- Angular distribution (1)
- Anion Transport System (1)
- Anisotropic flow (1)
- Anisotropie (1)
- Annihilation (1)
- Anregung (1)
- Anti de Sitter space (1)
- Anti-kaon–nucleon physics (1)
- Anti-nuclei (1)
- Antimatter (1)
- Antimicrobial resistance (1)
- Aptamer (1)
- Arms (1)
- Artificial Intelligence (1)
- Astronomical masses & mass distributions (1)
- Astrophysics (1)
- Asymmetrie Reconstitution (1)
- Atmosphere (1)
- Atomic & molecular beams (1)
- Atomic Physics (1)
- Atomic nuclei (1)
- Atomphysik (1)
- Atoms (1)
- Attenuated Total Reflection (1)
- Attosecond science (1)
- Auditory cortex (1)
- Autophagic cell death (1)
- BCS phase (1)
- BESIII detector (1)
- Bacterial structural biology (1)
- Band 3 Protein (1)
- Baryon number susceptibilities (1)
- Baryonic resonances (1)
- Beam Dynamic (1)
- Beam dynamics simulation (1)
- Beam loss (1)
- Beam techniques (1)
- Beer (1)
- Bell theorem (1)
- Beryllium-7 (1)
- Beschleunigung von Elektronen und Protonen (1)
- Beta decay (1)
- Betatrons (1)
- Betatronstrahlung (1)
- Bidirectional connections (1)
- Bilderkennung (1)
- Bildladung (1)
- Binary (1)
- Binary Neutron Star Mergers (1)
- Binary pulsars (1)
- Biochemical simulations (1)
- Bioenergetics (1)
- Biological locomotion (1)
- Biological physics (1)
- Biological sciences (1)
- Biomedical engineering (1)
- Biomoleküle (1)
- Biophysical chemistry (1)
- Bjorken flow (1)
- Black Holes (1)
- Blei (1)
- Bohmian mechanics (1)
- Boltzmann-Gleichung (1)
- Boltzmann-Vlasov equation (1)
- Boosted Jets (1)
- Born cross section measurement (1)
- Bose-Einstein condensates (1)
- Bose–Einstein condensation (1)
- Bosonisierung (1)
- Bottomonium (1)
- Bubble-like structure (1)
- Bulk viscosity (1)
- CBM detector (1)
- CERN PSB (1)
- CERN SPS (1)
- CH-Struktur (1)
- CJT formalism (1)
- CJT-Formalismus (1)
- CLVisc (1)
- CMOS (1)
- CMOS Monolithic Active Pixel Sensor (1)
- CNC manufacturing (1)
- CO2 emission reduction targets (1)
- COLTRIMS (1)
- COVID 19 (1)
- CP violation (1)
- CPS (1)
- CVD (1)
- Calcium ATPase (1)
- Calcium-ATPase (1)
- Canonical suppression (1)
- Cauchy horizon (1)
- Cell assembly (1)
- Centrality Class (1)
- Centrality Selection (1)
- Chaostheorie (1)
- Charge change (1)
- Charge fluctuations (1)
- Charge-transfer collisions (1)
- Charged-particle multiplicity (1)
- Charmed meson production (1)
- Charmonia (1)
- Charmonium (-like) (1)
- Charmonium decays (1)
- Chemical Physics (1)
- Chemiluminescence (1)
- Chemometry (1)
- Cherenkov counter: lead-glass (1)
- Chiral Lagrangian (1)
- Chiral Lagrangians (1)
- Chiral effective model (1)
- Chiral perturbation theory (1)
- Chirale Symmetrie (1)
- Chiralität (1)
- Chiralität, Elementarteilchenphysik (1)
- Chopper (1)
- Circular accelerators (1)
- Co2(CO)8 (1)
- Coincidence measurement (1)
- Cold nuclear matter effects (1)
- Collective Flow, (1)
- Collective flow (1)
- Collective quadrupole excitations (1)
- Collectivity (1)
- Collision processes (1)
- Color Glass Condensate (1)
- Color screening (1)
- Coltrims (1)
- Compact astrophysical objects (1)
- Compact binary stars (1)
- Compact objects (1)
- Comparison with QCD (1)
- Compressed Baryonic Matter (1)
- Compton scattering (1)
- Computational Data Analysis (1)
- Computational Physics (1)
- Computational biophysics (1)
- Computational models (1)
- Condensed Matter, Materials & Applied Physics (1)
- Conformational transitions (1)
- Conservation (1)
- Continuous Integration (1)
- Continuous wave (1)
- Correlated systems (1)
- Correlation (1)
- Correlations (1)
- Cortical circuit (1)
- Cosmology (1)
- Coulomb Explosion Imaging (1)
- Coulombdissoziation (1)
- Coulombexplosion (1)
- Coulombspaltung (1)
- Covariance matrix (1)
- Critical indices (1)
- Critical phenomena (1)
- Cross section measurements (1)
- Cross sections (1)
- Current-curent interaction (1)
- Czochralski method (1)
- D meson (1)
- D0 and D+ mesons (1)
- DEER or PELDOR (1)
- DLA Elektronen (1)
- DNA repair (1)
- DW Hamiltonian canonical transformation (1)
- Dalitz decay (1)
- Dark energy (1)
- Dark matter (1)
- Dark photon (1)
- Dark sector (1)
- Darmstadt / Gesellschaft für Schwerionenforschung (1)
- Data Standard (1)
- De Donder-Weyl Hamiltonian formulation (1)
- Deconfinement (1)
- Deep Learning (1)
- Deep learning (1)
- Delaunay-Triangulierung (1)
- Delayline Detector (1)
- Delta resonance (1)
- Dense matter (1)
- Dense nuclear matter (1)
- Density functional theory (1)
- Design, synthesis and processing (1)
- Detektor (1)
- Detektorentwicklung (1)
- Deuteronen (1)
- Di-hadron correlations (1)
- Diabetes (1)
- Diamagnetism (1)
- Diamantdetektor (1)
- Dielectron (1)
- Diffraction (1)
- Diffusion coefficient (1)
- Dimere (1)
- Dipol-Dipol-Wechselwirkung (1)
- Direct nuclear reactions (1)
- Direct reactions (1)
- Directed and elliptic flow (1)
- Discontinous Galerkin methods for Numerical Relativity (1)
- Diseases (1)
- Doppler radar (1)
- Double-sided silicon microstrip detectors characterization readout quality assurance (1)
- Drift Tube Linac (1)
- Drip-line nucleus (1)
- Dual projection (1)
- Duality (1)
- Dynamic transport (1)
- Dynamical critical phenomena (1)
- Dynamical mean field theory (1)
- Dynamical systems (1)
- Dynamischer Strukturfaktor (1)
- Dünnschichttransistor (1)
- D⁰ meson (1)
- EBID (1)
- EPR spectroscopy (1)
- Effective Field Theories (1)
- Effective Field Theory (1)
- Effective QCD model (1)
- Effective hadron theories (1)
- Eichtheorie (1)
- Eingebettetes optisches System (1)
- Einplatinene Kamera (1)
- Einstein’s equations (1)
- Elastic scattering (1)
- Electric and magnetic field computation (1)
- Electrical and electronic engineering (1)
- Electrical conductivity (1)
- Electromagnetic amplitude (1)
- Electromagnetic form factor (1)
- Electromagnetic form factors (1)
- Electromagnetic transitions (1)
- Electron capture (1)
- Electron-pion identification (1)
- Electronic transitions (1)
- Elektrodenarray (1)
- Elektron ; Impulsverteilung ; Heliumion (1)
- Elektronenanlagerungsreaktion (1)
- Elektronenwolke (1)
- Elektrostatik (1)
- Elementarteilchen (1)
- Elsevier (1)
- Emissionsspektroskopie (1)
- Emittanzmessung (1)
- Energietransduktion (1)
- Energy transfer (1)
- Entwicklungspsychologie (1)
- Enzyme mechanisms (1)
- Epidemiological statistics (1)
- Epidemiology (1)
- Equation of State (1)
- Equations of state: nuclear matter (1)
- Erythrocyte Membrane (1)
- EuB6 (1)
- European electricity grid (1)
- Event-by-event (1)
- Evolution of the Universe (1)
- Evolutionäre Spieltheorie (1)
- Excitation (1)
- Excluded volume (1)
- Exotic State (1)
- Exotic phases of matter (1)
- Exotica (1)
- Experimental testing (1)
- Experimental tests (1)
- FLASH Effekt (1)
- FM radar (1)
- FRW spacetime (1)
- FTAM and OX063 (1)
- Fahrzeug (1)
- Far from equilibrium (1)
- Faraday-Tasse (1)
- Feldeffekt (1)
- Feldeffekttransistor (1)
- Feldquant (1)
- Feldtheorie (1)
- Femtoscopy (1)
- Femtosekundenspektroskopie (1)
- Fermions (1)
- Fermion–gauge-boson vertex (1)
- Ferroelectrics and multiferroics (1)
- Fibre/foam sandwich radiator (1)
- Field Theories in Lower Dimensions (1)
- Field-effect (1)
- Filterkanal (1)
- Final state (1)
- Finite baryon density (1)
- Finite difference method (1)
- Finite element simulations (1)
- Finite-Differenzen (1)
- Finite-temperature QFT (1)
- First order phase transitions (1)
- Fission (1)
- Fixed-target experiments (1)
- Flavor changing neutral currents (1)
- Flavor symmetries (1)
- Flavour Physics (1)
- Flexible backup power (1)
- Floquet theory (1)
- Fluctuation Spectroscopy (1)
- Fluctuations in the initial conditions (1)
- Fluctuations of conserved charges (1)
- Fluid dynamics (1)
- Fluka (1)
- Fluktuationsspektroskopie (1)
- Fluoreszenz (1)
- Form factors (1)
- Formulations of Einstein Field Equations (1)
- Fourier transform spectroscopy (1)
- Fractal dimension (1)
- Fragmentierungsquerschnitte (1)
- Franck-Condon (1)
- Frankfurt <Main> / Institut für Kernphysik (1)
- Free energy (1)
- Free neutron targ (1)
- Free-Electron-Laser (1)
- Free-electron lasers (1)
- Freeze-out (1)
- Freezeout (1)
- Freie-Elektronen-Laser (1)
- Friedman equation (1)
- Fringe field (1)
- Fullerene (1)
- Funktionale Renormierungsgruppe (1)
- GEANT (1)
- GEM (1)
- GRMHD (1)
- Gabor Lens (1)
- Galaxies and clusters (1)
- Gamma intensity (1)
- Gamma spectroscopy (1)
- Gammakalorimeter (1)
- Gammaspectroscopy (1)
- Gap field (1)
- Gauge theories (1)
- GdIr2Si2 (1)
- Gefangenendilemma (1)
- Gehirn (1)
- Gene expression analysis (1)
- General Physics (1)
- General properties of QCD (dynamics, confinement, etc.) (1)
- General relativistic hydrodynamics (1)
- General relativity equations & solutions (1)
- Generalized uncertainty (1)
- Genetic engineering (1)
- Geometrical optics (1)
- Germanium detectors (1)
- Gesellschaft für Schwerionenforschung (1)
- Gittereichtheorie (1)
- Glauber and Giessen Boltzmann–Uehling–Uhlenbeck (GiBUU) models (1)
- Glimmentladung (1)
- Global polarization (1)
- Globale Optimierung (1)
- Gluons (1)
- Goldstone bosons (1)
- Graphene (1)
- Graphentheorie (1)
- Gravitational Waves (1)
- Gravitational collapse (1)
- Gravitational fixed point (1)
- Gravitational wave (1)
- Gravitational wave events (1)
- Gravity self-completeness (1)
- Groomed jet radius (1)
- Ground-state transition width (1)
- Großhirnrinde (1)
- HADES <Teilchendetektor> ; Driftkammer ; Ausleseverfahren <Sensortechnik> (1)
- HBT correlation (1)
- HBT interferometry (1)
- HBT puzzle (1)
- HEDP (1)
- HITRAP (1)
- HLT (1)
- Hades (1)
- Hadron Spectroscopy (1)
- Hadron potentials (1)
- Hadron production (1)
- Hadron resonance gas (1)
- Hadron spectroscopy (1)
- Hadron-Hadron Scattering Heavy (1)
- Hadronenjet (1)
- Hadronic potential (1)
- Hadronization (1)
- Hadrons (1)
- Hagedorn Zustände (1)
- Hagedorn states (1)
- Halbleiterdetektor (1)
- Hallsensor (1)
- Hard Scattering (1)
- Hawking radiation (1)
- Heavy Ion Experiment (1)
- Heavy Ion Physics (1)
- Heavy flavor production (1)
- Heavy flavour production (1)
- Heavy ion (1)
- Heavy ion storage ring (1)
- Heavy ions (1)
- Heavy quarks (1)
- Heavy-Ion Collision (1)
- Heavy-flavour decay muons (1)
- Heavy-ion physics (1)
- Heavy-ion reactions (1)
- Heavy-ions (1)
- Heavy-quark symmetry (1)
- Heisenberg modell (1)
- Heisenberg-Modell (1)
- Helium (1)
- Heliumdimere (1)
- Herzberg-Teller (1)
- High Energy Physics - Experiment (hep-ex) (1)
- High Energy Physics - Lattice (hep-lat) (1)
- High Energy Physics - Phenomenology (hep-ph) (1)
- High Energy Physics - Theory (hep-th) (1)
- High-Level Trigger (1)
- High-energy astrophysics (1)
- High-energy neutron detection (1)
- High-energy photoabsorption (1)
- High-k dielectric (1)
- High-k-Dielektrikum (1)
- Hirnforschung (1)
- Historie (1)
- Hochenergiephysik (1)
- Hochfrequenzsputtern (1)
- Hochstrom-Ionenquelle (1)
- Holography (1)
- Homeostasis (1)
- Hybrid Monte Carlo algorithm (1)
- Hybrid model (1)
- Hydrodynamic (1)
- Hydrodynamic models (1)
- Hydrodynamics (1)
- Hydrogen ground state (1)
- Hyperonic stars (1)
- ICD (1)
- IHMCIF (1)
- IPGLASMA (1)
- Image Charge (1)
- Image processing (1)
- Imaginary chemical potential (1)
- Immunology (1)
- Impact parameter (1)
- Impulsspektrometer (1)
- In-medium pion mass (1)
- Inclusive Reconstruction (1)
- Inclusive branching fraction (1)
- Inclusive spectra (1)
- Infections (1)
- Information theory and computation (1)
- Infrared Spectra (1)
- Infrared light (1)
- Infrared spectroscopy (1)
- Initial state (1)
- Innovative systems (1)
- Integrative Modeling (1)
- Integrator (1)
- Intensity interferometry (1)
- Interference fragmentation function (1)
- Interferometrie (1)
- Intermittency (1)
- Internet (1)
- Interstellar molecules (1)
- Invariant Mass Distribution (1)
- Inverse Kinematics (1)
- Invisible decays (1)
- Ion Beam (1)
- Ion-Atom-Kollisions (1)
- Ion-Molecule collisions (1)
- Ion-Molekül-Stoß (1)
- Ionbeam (1)
- Ionenquelle (1)
- Ionenstoß (1)
- Ionisation energy loss (1)
- Ions (1)
- Iron pnictides (1)
- Irregular plate (1)
- Irregular plate with non-uniform thickness (1)
- Isospin (1)
- J/ψ (1)
- J/ψ suppression (1)
- Jet Physics (1)
- Jet Substructure (1)
- Jet quenching (1)
- Jet shapes (1)
- Jet substructure (1)
- Josephson junction arrays (1)
- K+-nucleus interaction (1)
- K0S (1)
- KN interaction (1)
- Kagome systems (1)
- Kalman-Filter (1)
- Kaonic nuclei (1)
- Keldysh-Formalismus (1)
- Kernphysik (1)
- Kinetic Theory (1)
- Kitaev model (1)
- Kleines Molekül (1)
- Kohlenstoff (1)
- Kohlenstoffmolekül (1)
- Kollektive Anregung (1)
- Konformationsübergänge (1)
- Kooperativität (1)
- Kupfer-63 (1)
- LINAC (1)
- LaTeX (1)
- Lamb waves (1)
- Lambda Hyperon (1)
- Laminar flow (1)
- Langmuir-Blodgett monolayer (1)
- Langsame Extraktion (1)
- Lattice Gauge Theory (1)
- Lattice gauge field theories (1)
- Lattice gauge theory (1)
- Lattice simulations (1)
- Laute (1)
- Leptons (1)
- Levelized cost of electricity (1)
- Li-ion batteries (1)
- Li1.3Nb0.3Mn0.4O2 (1)
- Ligand-gated ion channel (1)
- Light (1)
- Light (anti-)(hyper-)nuclei production (1)
- Light nuclei production (1)
- Linac (1)
- Linear accelerator (1)
- Linear response (1)
- Linearer Collider ; Hohlraumresonator ; Moden (1)
- Linearer Collider ; Hohlraumresonator ; Moden ; Dämpfung ; Güte <Schwingkreis> ; Messung (1)
- Lipids (1)
- Lithium-7 (1)
- Longitudinal and transverse electric fields (1)
- Longitudinal flow (1)
- Low & intermediate energy heavy-ion reactions (1)
- Low & intermediate-energy accelerators (1)
- Low energy QCD (1)
- Luttinger liquid (1)
- Luttinger-Flüssigkeit (1)
- MYRRHA (1)
- Mach cones (1)
- Magnetfeld (1)
- Magnetfeldregelung (1)
- Magnetism (1)
- Magnetohydrodynamics (1)
- Magnetspektrometer (1)
- Magnons (1)
- Magon-Phonon-Wechselwirkung (1)
- Many-body (1)
- Many-body physics (1)
- Mars (1)
- Master Equations (1)
- Material budget (1)
- Materials science (1)
- Mathematical biosciences (1)
- Mathematics and computing (1)
- Maxwell–Chern–Simons (1)
- Md simulations (1)
- Mechanical engineering (1)
- Membrane and lipid biology (1)
- Membrane fusion (1)
- Membrane proteins (1)
- Membrane structures (1)
- Membrane transport (1)
- Membranes (1)
- Membranproteine (1)
- Meson decays (1)
- Meson production (1)
- Meson-exchange model (1)
- Mesons (1)
- Metasurfaces (1)
- Micro Vertex Detector (1)
- Microscopic quark–gluon string transport model (1)
- Mid-rapidity (1)
- Mikroelektrode (1)
- Mikrokanalelektronenvervielfacher (1)
- Minimum Bias (1)
- Models & methods for nuclear reactions (1)
- Models of QCD (1)
- Modified gravity (1)
- Molecular clouds (1)
- Molecular dynamics (1)
- Molecule destruction (1)
- Molecule formation (1)
- Molekularbewegung (1)
- Molekularstrahlepitaxie (1)
- Molekülphysik (1)
- Molekülstoß (1)
- Molybdän (1)
- Momentum Spectrometry (1)
- Monte Carlo (1)
- Monte Carlo simulation (1)
- Monte-Carlo simulations (1)
- Mott insulator (1)
- Mott metal-insulator transition (1)
- Mott transition (1)
- Multi-Parton Interactions (1)
- Multi-neutron detection (1)
- Multi-strange baryons (1)
- Multi-wire proportional drift chamber (1)
- Multigrid Poisson Solver (1)
- Multigrid methods (1)
- Multimessenger (1)
- Multiple Charge Conservation (1)
- Multiple parton interactions (1)
- Multivariate Analysis (1)
- NADH:ubiquinone oxidoreductase (1)
- Nambu–Goldstone bosons (1)
- Nambu–Jona-Lasinio model (1)
- Nanophotonics and plasmonics (1)
- Nanowires (1)
- Natrium-Kalium-ATPase (1)
- Natural transformation (1)
- NbC (1)
- Network model (1)
- Network models (1)
- Netzhaut ; Nervenzelle ; Inhibition (1)
- Netzwerktopologie (1)
- Neural Networks (1)
- Neural net (1)
- Neural network (1)
- Neural networks (1)
- Neuronal plasticity (1)
- Neurons (1)
- Neuroscience (1)
- Neutrinos (1)
- Neutron physics (1)
- Neutron-induced reaction cross sections (1)
- Neutronenquelle (1)
- Neutronenspektrum (1)
- Neutronenstern (1)
- New magicity (1)
- Nicht-linearer Transport (1)
- Nichtinvasiv (1)
- Nichtlineare Optik (1)
- Nichtlineare Spektroskopie (1)
- Nickel-63 (1)
- Niedrige Dimensionen (1)
- Nobel prizes (1)
- Noether symmetries (1)
- Noise spectra (1)
- Non-Canonical Amino Acids (1)
- Non-coding RNA (1)
- Non-dipole (1)
- Non-perturbative QCD (1)
- Non-relativistic QED (1)
- Noncommutative black holes (1)
- Noncommutativity (1)
- Nonequilibrium dynamics (1)
- Nonflow (1)
- Nonlinear beam dynamics (1)
- Nonperturbative Effects (1)
- Nonperturbative effects in field theory (1)
- Nonrandom connectivity (1)
- Nuclear Astrophysics (1)
- Nuclear Experiment (nucl-ex) (1)
- Nuclear Theory (nucl-th) (1)
- Nuclear fragments production (1)
- Nuclear interactions (1)
- Nuclear physics of explosive environments (1)
- Nuclear structure & decays (1)
- Nucleosynthesis in explosive environments (1)
- Nucleosynthesis-Star (1)
- Nucleus (1)
- Nukleare Astrophysik (1)
- Nukleon (1)
- Nullter Schall (1)
- Numerical Renormalization Group (1)
- Numerical simulations (1)
- Nyquist noise (1)
- O(2) Modell (1)
- O(2) model (1)
- O(4) conjecture (1)
- One-nucleon removal (1)
- Ontogenie (1)
- Open Access (1)
- Open Charm (1)
- Optical properties (1)
- Optical properties and devices (1)
- Optimal mix of wind and solar PV (1)
- Optimierung (1)
- Optische Messung (1)
- Optische Tomographie (1)
- Optisches Potenzial (1)
- Orbital electron capture (1)
- Other nonperturbative calculations (1)
- Over-Barrier Modell (1)
- Oxidation (1)
- P-Typ-ATPasen (1)
- P-type ATPase (1)
- PDB-Dev (1)
- PDBx/mmCIF (1)
- PENELOPE (1)
- PHENIX <Teilchendetektor> (1)
- PYTHIA (1)
- Pairing reentrance (1)
- Palatini (1)
- Pandemics (1)
- Partial chemical equilibrium (1)
- Partial wave analysis (1)
- Particle & resonance production (1)
- Particle Dynamic (1)
- Particle multiplicity (1)
- Particle phenomena (1)
- Particleantiparticle correlations (1)
- Particles & Fields (1)
- Parton cascade BAMPS (1)
- Path integral duality (1)
- Pb–Pb (1)
- Pepperpot (1)
- Pepperpot-Messung (1)
- Peptides and proteins (1)
- Percolation theory (1)
- Permeation and transport (1)
- Perturbative methods (1)
- Pfadintegral (1)
- Phase (1)
- Phase diagram (1)
- Phase diagram of dense matter (1)
- Phasendiagramm (1)
- Phasenraum (1)
- Phasenumwandlung (1)
- Phasenübergänge (1)
- Photodioden (1)
- Photoionisation (1)
- Photon counting (1)
- Photon number noise (1)
- Photonen (1)
- Photophysics (1)
- Photophysik (1)
- Pickupspule (1)
- Pilus (1)
- Pixel detector (1)
- Planck scale (1)
- Plasma acceleration (1)
- Plasma membrane (1)
- Plasma physics (1)
- Plasmadiagnostik (1)
- Plasmons Quantum mechanics (1)
- Plastic scintillator array (1)
- Plasticity (1)
- Plates fractalization (1)
- PointNet (1)
- Poisson-Gleichung (1)
- Polarkoordinaten (1)
- Polyakov loops (1)
- Polyatomare Verbindungen (1)
- Polypeptide (1)
- Polypeptides (1)
- Population activity (1)
- Potassium transport (1)
- Probability distribution (1)
- Production Cross Section (1)
- Production mechanisms (1)
- Properties of Hadrons (1)
- Protein Dynamics (1)
- Protein Modifications (1)
- Protein Shape (1)
- Protein folding (1)
- Protein homeostasis (1)
- Proteine (1)
- Proton number fluctuations (1)
- Proton-proton collisions (1)
- Protonen (1)
- Protonen Linac (1)
- Protonengegentransport (1)
- Protonenplasmen (1)
- Proton–proton (1)
- Prototypes (1)
- Protyposis (1)
- Pseudorapidity and centrality dependence (1)
- Pulse Shape Analysis (1)
- Pulsed epr (1)
- Pygmy Dipole Resonance (1)
- Pygmy dipole resonance (1)
- Pygmy quadrupole resonance (1)
- QCD phase transitions (1)
- QCD vector interaction strength (1)
- QCD-phase diagram (1)
- QED (1)
- QFT on curved background (1)
- Quantenphysik (1)
- Quantenspinsystem (1)
- Quantentheorie (1)
- Quantum Impurity System (1)
- Quantum corrected black hole (1)
- Quantum electrodynamics (1)
- Quantum information (1)
- Quantum modified Gravity (1)
- Quantum phase transitions (1)
- Quark <Physik> (1)
- Quark Deconfinement (1)
- Quark Gluon Plasma (1)
- Quark Production (1)
- Quark gluon plasma (1)
- Quark-gluon Plasmap (1)
- Quark-gluon-plasma (1)
- Quasi-particle phonon model (1)
- Quasiteilchen (1)
- R value (1)
- RFQ-Accelerator (1)
- RFQ-Beschleuniger (1)
- RNA (1)
- RNA structures (1)
- Radiation Tolerance (1)
- Radiation detectors (1)
- Radiation hardness (1)
- Radiative decay (1)
- Radiative decays (1)
- Radiative transfer (1)
- Radio continuum emission (1)
- Radio jets (1)
- Rain (1)
- Random fields (1)
- Random graph model (1)
- Rapidity Range (1)
- Rare decays (1)
- Ratengleichungen (1)
- Reaction Kinetics (1)
- Reactions with relativistic radioactive beams (1)
- Reaktionskinetik (1)
- Reaktionsmikroskop (1)
- Recombination (1)
- Recombination of partons (1)
- Reconstructed jets (1)
- Regelungssystem (1)
- Regeneration (1)
- Relativistic Dissipative Hydrodynamics (1)
- Relativistic Heavy Ions (1)
- Relativistic Heavy-ion Collisions (1)
- Relativistic heavy ion physics (1)
- Relativistic heavy-ion reactions (1)
- Relativistic nuclear collisions (1)
- Relativistische Hydrodynamik (1)
- Relaxation time approximation (1)
- Renewable power generation (1)
- Renormalization group (1)
- Renormierungsgruppe (1)
- Representational drift (1)
- Resolution Parameter (1)
- Resonance reactions (1)
- Resonances (1)
- Riccati equation (1)
- Richardson extrapolation (1)
- Robotic behavior (1)
- Robots (1)
- Rudder stock (1)
- Rydberg (1)
- SIS18 (1)
- SMASH (1)
- SPS (1)
- STAR (1)
- STAR <Teilchendetektor> (1)
- SYK model (1)
- Sachunterricht (1)
- Saha equation (1)
- Scale invariance (1)
- Scaling laws (1)
- Scattering of atoms, molecules, clusters & ions (1)
- Scattering theory (1)
- Scattering-type Scanning Near-field Optical Microscopy (1)
- Schaum (1)
- Schlitz-Gitter (1)
- Schottky (1)
- Schulbuchanalyse (1)
- Schwerionen (1)
- Schwerionenstrahl (1)
- Schwerpunkthöhe (1)
- Schwinger effect (1)
- Schwinger–Dyson equations (1)
- Schätzverfahren (1)
- Scintillation (1)
- Secondary beams (1)
- Secretin (1)
- Sehrinde (1)
- Seiberg–Witten map (1)
- Sekundärelektronen (1)
- Selbstorganisation (1)
- Self absorption (1)
- Self-dual (1)
- Self-triggered front-end electronics (1)
- Semi-leptonic decays (1)
- Sensors (1)
- Septum (1)
- Shakhov model (1)
- Shield (1)
- Shock Waves (1)
- Short-lived nuclei (1)
- Signalanalyse (1)
- Silicon Tracking System (1)
- Silicon tracking system (1)
- Simulation and modeling (1)
- Single muons (1)
- Single particle decay spectroscopy (1)
- Single-molecule biophysics (1)
- Slavkovska (1)
- Small systems (1)
- Social distancing (1)
- Social systems (1)
- Sodium-potassium ATPase (1)
- SoftDrop (1)
- Solar power (1)
- Solar power generation (1)
- Solid state theory (1)
- Spectators (1)
- Spectroscopic factors & electromagnetic moments (1)
- Spektroskopie (1)
- Spieltheorie (1)
- Spin Hall (1)
- Spin alignment (1)
- Spin distribution and correlation (1)
- Spin-down (1)
- Spin-orbit coupling (1)
- Spintronics (1)
- Spinwaves (1)
- Spinwelle (1)
- Spinwellen (1)
- Splitting function (1)
- Spontaneous symmetry breaking (1)
- Sputtern (1)
- SrNi2P2 (1)
- Stahlenschäden (1)
- Statistical Physics (1)
- Statistical and Nonlinear Physics (1)
- Statistical model (1)
- Statistical models (1)
- Statistical multifragmentation models (1)
- Statistical theory and fluctuations (1)
- Statistische Physik (1)
- Stellar remnants (1)
- Stellar structure (1)
- Storage Ring (1)
- Storage rings (1)
- Stoß (1)
- Strahldiagnose (1)
- Strahldiagnosemethode (1)
- Strange hadrons (1)
- Strangeness Enhancement (1)
- Strangeness production (1)
- String T-duality (1)
- Strong amplitude (1)
- Strong coupling expansion (1)
- Strongly-coupled plasmas (1)
- Structural biology (1)
- Störungstheorie (1)
- Stößparameter (1)
- Sub-wavelength optics (1)
- Sulfur Dioxide (1)
- Superconducting devices (1)
- Supercooled QGP (1)
- Supermassive black holes (1)
- Supernova (1)
- Supernova remnant (1)
- Surfaces, interfaces and thin films (1)
- Surrogate-reaction method (1)
- Susceptibilities (1)
- Synapses (1)
- Synchronisierung (1)
- Systematic Uncertainty (1)
- Szintillation (1)
- Szintillationsschirm (1)
- Säugling (1)
- TATA box binding protein (1)
- THz (1)
- THz detection (1)
- THz imaging (1)
- TNSA (1)
- TPC (1)
- TPSC (1)
- TR (1)
- Techniques Electromagnetic calorimeters (1)
- Techniques and instrumentation (1)
- Teilchendynamik (1)
- Template (1)
- Terahertz optics (1)
- Theoretical and experimental femtoscopy (1)
- Theoretical and experimental identical-particle correlations (1)
- Theoretical neuroscience (1)
- Theoretical nuclear physics (1)
- Theoretical physics (1)
- Thermal & statistical models (1)
- Thermal Field Theory (1)
- Thermal evolution (1)
- Thermal lensing (1)
- Thermalization (1)
- Thermo optic effects (1)
- Thermodynamik (1)
- Thermoplasma acidophilum (1)
- Thermoplasma volcanium (1)
- Thermus thermophilus (1)
- Theta-Pinch (1)
- Thin film transistor (1)
- Thin lens (1)
- Three-gluon vertex (1)
- Time Projection Chamber (1)
- Time Projection Chamber (TPC) (1)
- Time-Resolved Spectroscopy (1)
- TmRh2Si2 (1)
- Tomographie (1)
- Topological insulators (1)
- Topologische Zustände (1)
- Topology (1)
- Tracking (1)
- Transient & explosive astronomical phenomena (1)
- Transimpedanzverstärker (1)
- Transition Radiation Detector (1)
- Transition radiation detector (1)
- Transport (1)
- Transport Simulations (1)
- Transport Theory (1)
- Transport model (1)
- Transport model for heavy-ion collisions (1)
- Transport phenomena (1)
- Transverse momentum (1)
- Transversity (1)
- Trigger (1)
- Triple quarkonia (1)
- Tumortherapie (1)
- Two body weak decay (1)
- UWB diagnostics (1)
- Ultrafast laser spectroscopy (1)
- Ultrafast spectroscopy (1)
- Ultrakalte Quantengase (1)
- Un-particle physics (1)
- Unparticle parameter constraints (1)
- Unparticle physics (1)
- Unparticles (1)
- Unruh effect (1)
- Unstable nuclei induced nuclear reactions (1)
- UrQMD (1)
- Vakuum (1)
- Vakuumphysik (1)
- Vector Boson Production (1)
- Very long baseline interferometry (1)
- Vesicle fusion (1)
- Vesicles (1)
- Vibrational Energy Transfer (1)
- Virtual reality (1)
- Visible spectroscopy (1)
- Visual cortex (1)
- Vortex ratchets (1)
- Vorticity (1)
- W-exchange (1)
- Ward–Green–Takahashi identities (1)
- Wasserstoffatmosphäre (1)
- Wasserstoffmolekül ; Heliumion ; Ion-Molekül-Stoß ; Rückstoßimpulsspektroskopie (1)
- Weak Decays (1)
- Weak interactions (1)
- Wigner function (1)
- Wind power (1)
- Wind power generation (1)
- Worldwide Protein Data Bank (1)
- X(3872) (1)
- X-ray crystallography (1)
- X-ray generation (1)
- X-ray irradiation (1)
- X-ray phase contrast imaging (1)
- X-ray spectroscopy (1)
- X-rays (1)
- Xenon-based gas mixture (1)
- Y (4260) (1)
- Y states (1)
- Yang-Mills-Theorie (1)
- YbNi4P2 (1)
- YbRh2Si2 (1)
- Yttrium-Eisengranat (1)
- Zero crossing (1)
- Zero-point length (1)
- Zerstörungsfrei (1)
- Zr (1)
- a-induced reactions (1)
- absorbed power (1)
- abundances (1)
- accelerator physics (1)
- activation (1)
- active perception (1)
- adhesion (1)
- adsorption (1)
- algebraic cluster model (1)
- ambiguous perception (1)
- ambiguous structure-from-motion (SFM) (1)
- anisotropic flow (1)
- antiviral signaling (1)
- application (1)
- applications of teraherz imaging (1)
- archaea (1)
- artificial magnetic lattices (1)
- astrophysikalischer p-Prozess (1)
- asymptotic behavior (1)
- atomic cluster deposition (1)
- atomic cluster on a suface (1)
- atomic physics (1)
- attosecond spectroscopy (1)
- automotive (1)
- autonomous learning (1)
- axions (1)
- bacteriorhodopsin reconstitution (1)
- band insulator (1)
- baryon stopping (1)
- beam energy scan (1)
- beam transport (1)
- behavioral performance (1)
- bilayer square lattice (1)
- bilinear model (1)
- bilineares Modell (1)
- binary systems (1)
- binocular rivalry (1)
- binocular vision (1)
- bistability (1)
- black hole (1)
- black lipid membrane (1)
- blue bronze (1)
- branching fractions (1)
- brightness (1)
- bulk observables (1)
- bunch-to-bucket (1)
- calorimeter: electromagnetic (1)
- capture processes (1)
- causality (1)
- cell internal structure (1)
- cell respiration (1)
- center-of-mass energy (1)
- central schemes (1)
- centrality (1)
- centrality dependence (1)
- change detection (1)
- chaos (1)
- charcoal (1)
- charge density wave (1)
- charge-cluster glass (1)
- charged kaon freeze-out (1)
- charmed baryon (1)
- charmonium-like states (1)
- chemical vapor deposition (1)
- children (1)
- chiral effect (1)
- chiral imbalance (1)
- chiral perturbation theory (1)
- chromium (1)
- circadian rhythm (1)
- class separation (1)
- clathrates (1)
- closed orbit feedback system (1)
- closed-loop robots (1)
- cluster expansion model (1)
- cobalt (1)
- cognition (1)
- coherent emission (1)
- coherent state (1)
- coincidence detection (1)
- collective flow (1)
- commissioning (1)
- communication networks (1)
- compact binary mergers (1)
- complex networks (1)
- complex systems (1)
- compliant robot (1)
- computational imaging (1)
- computational methods (1)
- confinement (1)
- continuum model (1)
- correlations and fluctuations (1)
- cortex (1)
- cosmology (1)
- coupled oscillators (1)
- covariant canonical gauge gravity (1)
- covariant canonical gauge theory of gravity (1)
- critical point (1)
- crowd behaviour (1)
- crystal growth (1)
- curvature-dependent fermion mass (1)
- cyclotron (1)
- dE/dx (1)
- damage detection (1)
- dark matter (1)
- dark matter experiments (1)
- data traffic (1)
- decay (1)
- decays (1)
- decelerated ions (1)
- decision making (1)
- deconfinement (1)
- dendrites (1)
- dense plasma target (1)
- density (1)
- deposition (1)
- deposition; dissociation; electron beam induced deposition (EBID); focused electron beam induced deposition (FEBID); precursor; trimethyl(methylcyclopentadienyl)platinum(IV) ((CH3-C5H4)Pt(CH3)3) (1)
- desorption (1)
- detector characterization (1)
- detectors (1)
- development (1)
- diagnostics (1)
- diffractive optics (1)
- diffusion model (1)
- digital communications (1)
- dimuon (1)
- diphoton (1)
- dipole-dipole interaction (1)
- direct-write fabrications (1)
- dissipative fluid dynamics (1)
- dissociation (1)
- dissociative electron attachment (1)
- dissociative ionization (1)
- dynamical Higgs effect (1)
- dynamical mean-field theory (1)
- e+e − annihilation (1)
- e+e⁻ − Experiments (1)
- e+e− Experiments (1)
- e+e− annihilation (1)
- early diabetes detection (1)
- echo-state networks (1)
- effective field theories (1)
- effective field theory (1)
- effective temperature (1)
- efficient coding (1)
- electric field (1)
- electrical characterization (1)
- electrical tests (1)
- electrical transport characteristics (1)
- electro-magnetic plasma (1)
- electromagnetic fields (1)
- electromagnetic orbital angular momentum (1)
- electromagnetic probes (1)
- electromagnetic vorticity (1)
- electromechanical impedance (1)
- electron (1)
- electron backscattering (1)
- electron induced deposition (1)
- electron molecule interaction (1)
- electron transfer (1)
- electron transport (1)
- electron tunneling (1)
- electron-lattice coupling (1)
- electron-phonon interactions (1)
- electron-positron collision (1)
- electronic structure (1)
- electronics: readout (1)
- electron–phonon coupling (1)
- electron−phonon interactions (1)
- electrostatics (1)
- elsarticle.cls (1)
- emerging length (1)
- emittance (1)
- emotion theory (1)
- endoplasmic reticulum (1)
- endothelial cells (1)
- energy-dispersive x-ray spectroscopy (1)
- entropy limited hydrodynamics (1)
- envy (1)
- estimation methods (1)
- eta meson (1)
- evacuation (1)
- event pileup (1)
- exact exchange (1)
- excess kurtosis (1)
- excitation (1)
- excitation transport (1)
- excited nuclei (1)
- experimental results (1)
- extended Einstein gravity (1)
- extra dimensions (1)
- famotidine (1)
- faraday cup (1)
- fatigue testing (1)
- feelings (emotions) (1)
- fibre: optical (1)
- field-effect transistor (1)
- field-effect transistors (1)
- filter channel (1)
- finite baryon density (1)
- finite-temperature quantum-field theory (1)
- first order phase transition (1)
- flow allocation (1)
- flow anisotropies (1)
- fluctuation spectroscopy (1)
- fluctuations (1)
- fluctuations and correlations (1)
- flux growth (1)
- flux limiters (1)
- focused electron beam (1)
- focused electron beam-induced deposition (1)
- focused ion beam induced depositions (1)
- focused-electron-beam-induced deposition (FEBID); Monte Carlo simulation of electron transport; surface excitations; secondary-electron emission (1)
- formation length (1)
- free will (1)
- frequency beating (1)
- fullerene (1)
- functional principal component analysis (1)
- galactic chemical evolution (1)
- gamma) Reaktionen (1)
- gamma) reactions (1)
- gasous detectors (1)
- gauge theory (1)
- gauge/gravity duality (1)
- general relativity (1)
- generalized uncertainty principle (1)
- generative model (1)
- generatives Modell (1)
- genetic algorithm (1)
- geodesic equation (1)
- glass fiber reinforced materials (1)
- glass-like structural ordering (1)
- gold (1)
- granular ferromagnets (1)
- granulare Metalle (1)
- graph theory (1)
- graphene (1)
- gravitation (1)
- guiding principle (1)
- hadron spectroscopy (1)
- hadron transport (1)
- hadron-quark phase transition (1)
- hadronic events (1)
- half-integer resonance (1)
- heat shock protein (1)
- heavy fermions (1)
- heavy ion collision (1)
- heavy ion experiments (1)
- heavy ion fusion (1)
- heavy-ion (1)
- heavy-ion collision (1)
- heavy-ion collisions; (1)
- heavy-ion physics (1)
- heavy-ion storage rings (1)
- heavy-ions (1)
- heavy-quark effective theory (1)
- height of COG (1)
- helicity amplitude analysis (1)
- helium dimers (1)
- helium-beam radiography (1)
- hematological (1)
- heteronuclear FEBID precursors (1)
- hheterostructures (1)
- high (1)
- high energy astrophysics (1)
- high-Tc superconductivity (1)
- high-energy physics (1)
- high-resolution momentum spectroscopy (1)
- higher twist effects (1)
- highly parallel recordings (1)
- highly-charged ions (1)
- histamine (1)
- homeostasis (1)
- human intracranial recordings (1)
- human-body radiation (1)
- hybrid (1)
- hybrid star (1)
- hydrogen atmosphere (1)
- hydrogen energy levels (1)
- hypernuclear (1)
- impact parameter (1)
- in situ processing (1)
- in-medium modification (1)
- inclusive J/ψ decays (1)
- independent component analysis (1)
- inertia of spacetime (1)
- inertia of space–time (1)
- inertial confinement fusion (1)
- infancy (1)
- inflammation (1)
- infrared laser test (1)
- infrared spectroscopy (1)
- injection system (1)
- instabilities (1)
- interactive visualization (1)
- interferometry (1)
- intermetallic compound (1)
- intra-dimer charge and spin degrees of freedom (1)
- intrinsic motivation (1)
- intrinsic plasticity (1)
- inverse kinematics (1)
- ion (1)
- ion stopping (1)
- ion-beam therapy (1)
- ionisierende Strahlung (1)
- ionizing radiation (1)
- ion–atom collisions (1)
- ion–molecule collisions (1)
- isospin (1)
- isospin asymmetric matter (1)
- isospin imbalance (1)
- isotopic abundance (1)
- jets (1)
- kagome lattices (1)
- kaltes Gastarget (1)
- kilonovae (1)
- kinematic collimation (1)
- kinematische Kollimation (1)
- kinetic approaches to dense matter (1)
- kinetic instabilities (1)
- large-scale integration of renewable power generation (1)
- large-scale integration of variable renewable generation (1)
- laser characterization (1)
- laser plasma emission (1)
- laser test (1)
- laser-ion acceleration (1)
- laser-matter interaction (1)
- lattice-supersolid (1)
- lawsHeavy-ion collisions (1)
- leukocytes (1)
- light harvesting networks (1)
- light nuclei (1)
- light nuclei production (1)
- light-driven ATP synthesis (1)
- light–energy conversion (1)
- limit cycles (1)
- line density (1)
- line element (1)
- linear sigma mode (1)
- liposomes (1)
- lithography (1)
- liver, pancreas (1)
- load and structural monitoring (1)
- local field potential (1)
- low dimensions (1)
- low-dose irradiation (1)
- low-mass dilepton (1)
- lower critical field (1)
- luminosity (1)
- machine learning (1)
- magnetic exchange beyond Heisenberg (1)
- magnetic nanostructures (1)
- magnetic nanowires (1)
- magnetic susceptibility (1)
- magnetism (1)
- magnon condensation (1)
- magnon-phonon interaction (1)
- magnon-phonon interactions (1)
- main phospholipid (1)
- malignancies (1)
- manganese (1)
- many particle entanglement (1)
- many-body blockade (1)
- many-body method (1)
- many-electron correlation (1)
- marine structures (1)
- mass degeneracy (1)
- mathematical model (1)
- maximum recoverable strain (1)
- membrane protein (1)
- membrane proteins (1)
- metal carbonyl (1)
- meteorological radar (1)
- metric tensor (1)
- micro Hall magnetometry (1)
- micro-Hall magnetometry (1)
- microdosimetry (1)
- micromagnetic simulations (1)
- micropillar compression (1)
- microwave breast imaging (1)
- millimeter wave radar (1)
- millimeter-wave spectroscopy (1)
- minimal length (1)
- model (1)
- modeling (1)
- modified Coulomb potential (1)
- moiré patterns (1)
- molecular electronic devices (1)
- molecular magnets (1)
- molecular modeling (1)
- molecular simulations (1)
- momentum spectrometer (1)
- monkeys (1)
- monte carlo simulations (1)
- multi-center magnons (1)
- multi-messenger (1)
- multi-orbital Hubbard model (1)
- multicoincidence imaging (1)
- multimessenger astrophysics (1)
- multiparton interactions (1)
- multiunit activity (1)
- mushroom instability (1)
- music charts (1)
- n,p,π and Λ+Σ0 production (1)
- nano-fabrication (1)
- nano-printing (1)
- nanocarbon (1)
- nanoelectronic devices (1)
- nanofractal formation (1)
- nanofractal fragmentation (1)
- nanolesions (1)
- nanolithography (1)
- nanomagnetism (1)
- nanoparticle (1)
- nanostructured arrays (1)
- nanotechnology (1)
- nash equilibrium (1)
- natural scenes (1)
- natural tasks (1)
- near-field microscopy (1)
- net-proton fluctuations (1)
- networks (1)
- neutral mesons (1)
- neutral pion (1)
- neutron - nuclear reactions (1)
- neutron star (1)
- neutron star collisions (1)
- neutron star properties (1)
- neutron stars; (1)
- neutron-induced reactions (1)
- neutron-star-merger (1)
- next-to-leading order perturbative QCD calculations (1)
- nickel (1)
- nnp (1)
- non-Condon (1)
- non-equilibrium states (1)
- non-invasive diagnosis techniques (1)
- non-invasive test (1)
- non-neutral plasma (1)
- non-perturbative methods (1)
- noncommutative geometry (1)
- nonequilibrium phase transitions (1)
- nonneutral plasma (1)
- nuclear (1)
- nuclear collective model (1)
- nuclear modification (1)
- nuclear reaction cross sections (1)
- nuclear reaction cross-sections (1)
- nucleon coalescence (1)
- nuklear matter (1)
- nukleare Wirkungsquerschnitte (1)
- number of J/ψ events (1)
- numerical methods (1)
- numerical relativity (1)
- observational cosmology (1)
- omega stringer (1)
- on imaging (1)
- on-chip solutions (1)
- one-photon double ionization (1)
- open guided waves (1)
- open quantum systems (1)
- operation (1)
- optimal wind/solar mix (1)
- optimization (1)
- optische Potentiale (1)
- optokinetic nystagmus (1)
- organic compounds (1)
- organic conductor (1)
- organic semiconductor (1)
- organotypic slice culture (1)
- oxygen vacancies (1)
- oxysterol-binding protein homology protein (1)
- p A¯ reactions (1)
- p+p collisions (1)
- p-Linac (1)
- packaging (1)
- parity-doublet model (1)
- particle-theory and field-theory models of the early universe (1)
- passive imaging (1)
- path integral (1)
- patient study (1)
- patterning (1)
- pauli principle (1)
- percolation (1)
- perovskite oxides (1)
- phase shift (1)
- phase transitions (1)
- phonon (1)
- phosphatidylinositol 4-phosphate 5-kinase (1)
- phosphatidylserine (1)
- photochemistry (1)
- photons (1)
- photopolymerization (1)
- piezoresistivity (1)
- plasma ion beam interaction (1)
- plasma membrane (1)
- plasmonics (1)
- plasticity (1)
- platinum (1)
- polar coordinates (1)
- polarization (1)
- polarized radiation (1)
- polarons (1)
- power system analysis; (1)
- ppK − (1)
- precursor (1)
- precursor residence time (1)
- predictive modelling (1)
- prefrontal cortex (1)
- presolar grain (1)
- pressure (1)
- pressure sensors (1)
- projectile effective charge (1)
- protein coevolution (1)
- protein complex (1)
- protein stability (1)
- protein structures (1)
- proton countertransport (1)
- proton flow (1)
- proton permeability (1)
- proton-proton (1)
- pseudoelasticity (1)
- pyramidal neuron (1)
- p¯ + 40Ar → 40 Cl + (1)
- quadratic Lagrangian (1)
- quadratic temperature dependent resistivity (1)
- quadrupole (1)
- quality assurance (1)
- quantum (1)
- quantum criticality (1)
- quantum dots (1)
- quantum electrodynamics test (1)
- quantum hydrodynamics (1)
- quantum measurement (1)
- quantum spin frustration (1)
- quantum spin liquids (1)
- quantum spin system (1)
- quantum transport (1)
- quark deconfinement (1)
- quark matter (1)
- quark-gluon plasma temperature (1)
- quark‐gluon plasm (1)
- quasiparticle expansion (1)
- quintessence (1)
- r-Prozess (1)
- r-process (1)
- radar detection (1)
- radar imaging (1)
- radar signal processing (1)
- radar-based structural health monitoring (1)
- radiation hard sensor (1)
- radon (1)
- rain (1)
- reaction rate (1)
- recurrent networks (1)
- recurrent neural networks (1)
- reference damage (1)
- relativistic astrophysics (1)
- relativistic boson system of particles and antiparticles (1)
- relativistic collisions (1)
- relativistic fluid dynamics (1)
- relativistic heavy ion reactions (1)
- relativity and gravitation (1)
- remote sensing by radar (1)
- resonance properties (1)
- resonant (1)
- reversible figures (1)
- rfq (1)
- robophysics (1)
- s-SNOM (1)
- saturation (1)
- scanning Hall probe microscopy (1)
- scanning laser Doppler vibrometry (1)
- scanning probe microscopy (1)
- science of sciences (1)
- self-organization (1)
- self-organized criticalit (1)
- self-organized criticality (1)
- self-organized locomotion (1)
- semiconductors (1)
- semiexclusive processes (1)
- sensorimotor loop (1)
- shear stress (1)
- sign problem (1)
- signal processing (1)
- silicon detector (1)
- silicon sensor (1)
- simulations (1)
- single crystal growth (1)
- single-shot measurement (1)
- site-directed spin labeling (1)
- slabs (1)
- slowness Lernen (1)
- slowness learning (1)
- small systems (1)
- smooth pursuit (1)
- social acceleration (1)
- social classes (1)
- social modelling (1)
- social stratification (1)
- sociophysics (1)
- soft photons (1)
- solar physics (1)
- space charge (1)
- space charge distortions (1)
- sparse coding (1)
- specific heat (1)
- spectators (1)
- spectra (1)
- spectral radius (1)
- spectroscopy (1)
- spike train analysis (1)
- spiking neural networks (1)
- spin labeling (1)
- spin polarization (1)
- spin wave (1)
- spintronics (1)
- spontaneous symmetry breaking (1)
- stability (1)
- stability matrix eigenvalues (1)
- starke Magnetfelder (1)
- statistical model (1)
- sterol (1)
- stimulus coding (1)
- storage ring (1)
- strain sensing (1)
- strangeness enhancement (1)
- strategy condensation (1)
- string T-duality (1)
- strong Coulomb field (1)
- strong correlations (1)
- strongly correlated electrons (1)
- strontium vanadate epitaxial films (1)
- structural biology (1)
- su(2) x u(2) (1)
- sub-threshold (1)
- subthreshold (1)
- superconducting devices (1)
- superconductivity (1)
- superconductor-to-metal transition (1)
- superdeterminism (1)
- supervised learning (1)
- supraleitend (1)
- surface plasmon polaritons (1)
- surface reconstruction (1)
- surface science (1)
- surface waves (1)
- surrogate reactions (1)
- sustained hyperglycemia (1)
- symmetry energy (1)
- synaptic scaling (1)
- synchronization (1)
- synchronization two rings (1)
- synchronized oscillators (1)
- synchrotron emission (1)
- synthetic aperture radar (1)
- target (1)
- terahertz emission (1)
- terahertz magnetometry (1)
- terahertz photons (1)
- terahertz sensing (1)
- teraherz imaging systems (1)
- teraherz nano-imaging and nanoscopy (1)
- tetraether lipid (1)
- tetraquark (1)
- tetraquarks (1)
- the Weibel instability (1)
- theoretical biology (1)
- theory mind (1)
- thermal expansion (1)
- thermal transition (1)
- thermoadaptation (1)
- thermodynamic functions and equations of state (1)
- thermodynamic properties (1)
- thermodynamics (1)
- thermoelectric material (1)
- thermoelectrics (1)
- theta-pinch (1)
- three-dimensional nanostructures (1)
- time scales (1)
- time series prediction (1)
- time-resolved (1)
- tip fabrication (1)
- toll-like receptor (1)
- top-down control (1)
- topological states (1)
- toroidales Magnetfeld (1)
- torsion (1)
- torsional dark energy (1)
- total cross-section (1)
- tracking (1)
- transient interaction (1)
- transmission cost allocation (1)
- transmission grid extensions (1)
- transport (1)
- transport models (1)
- transport models quark-gluon plasma (1)
- transvers beam dynamics (1)
- triangular flow (1)
- trigger efficiency (1)
- tungsten (1)
- two-electron systems (1)
- ultracold quantum gases (1)
- ultraperipheral and central heavy ion collisions (1)
- ultrashort laser pulses (1)
- unconventional superconductor (1)
- unsaturated phospholipid (1)
- van der Waals (1)
- vanadium (1)
- vanadium oxides (1)
- vapor-liquid-solid mechanism (1)
- variational Monte Carlo (1)
- vibronic (1)
- virtual photon emission (1)
- viscosity (1)
- viscous cosmology (1)
- viscous hydrodynamics (1)
- visual short-term memory (1)
- visual working memory (1)
- washboard pinning potential (1)
- white and brown dwarfs (1)
- wind (1)
- wind energy (1)
- wind turbine blades (1)
- wind turbines (1)
- wwPDB (1)
- x-ray techniques (1)
- yttrium-iron garnet (1)
- zero-point length (1)
- zerstörungsfrei (1)
- Θ+ pentaquark (1)
- Λ+c baryon (1)
- Λc⁺ (1)
- Σ hyperon (1)
- β-barrel assembly machinery (BAM) complex (1)
- γ-ray spectroscopy (1)
- γ-spectroscopy (1)
- η/s (1)
- κ meson (1)
- φ feed-down (1)
- ψ(3686) (1)
- √sN N = 2.76 TeV (1)
- field-effect transistor (1)
Institute
- Physik (3415) (remove)
The Compressed Baryonic Matter experiment (CBM) at FAIR and the NA61/SHINE experiment at CERN SPS aim to study the area of the QCD phase diagram at high net baryon densities and moderate temperatures using heavy-ion collisions. The FAIR and SPS accelerators cover energy ranges 2-11 and 13-150 GeV per nucleon respectively in laboratory frame for heavy ions up to Au and Pb. One of the key observables to study the properties of a matter created in such collisions is an anisotropic transverse flow of particles.
In this work, the performance of the CBM experiment for anisotropic flow measurements is studied with Monte-Carlo simulations using gold ions at SIS-100 energies employing different heavy-ion event generators. Also, procedures for centrality estimation and charged hadron identification are described and corresponding frameworks are developed.
The measurement of the reaction plane angle is performed with Projectile Spectator Detector (PSD), which is a hadron calorimeter located at a very forward angle. To prevent radiation damage by the high-intensity ion beam, the PSD has a hole in the center to let the beam pass through. Various combinations of CBM detector subsystems are used to investigate the possible systematic biases in flow and centrality measurements. Effects of detector azimuthal non uniformity and the PSD beam hole size on physics performance are studied. The resulting performance of CBM for flow measurements is demonstrated for identified charged hadron anisotropic flow as a function of rapidity and transverse momentum in different centrality classes.
The measurement techniques developed for CBM were also validated with the experimental data recently collected by the NA61/SHINE experiment at CERN SPS for Pb+Pb collisions at the beam momenta 30A GeV/c. Compared to the existing data from the NA49 experiment at the CERN SPS, the new data allows for a more precise measurement of anisotropic flow harmonics. The fixed target setup of NA61/SHINE also allows extending flow measurements available from the STAR at the RHIC beam energy scan (BES) program to a wide rapidity range up to the forward region where the projectile nucleon spectators appear. In this thesis, an analysis of the anisotropic flow harmonics in Pb+Pb collisions at beam momenta 30A GeV/c collected by the NA61/SHINE experiment in the year 2016 is presented. Flow coefficients are measured relative to the spectator plane estimated with the Projectile Spectators Detector (PSD). The flow coefficients are obtained as a function of rapidity and transverse momentum in different classes of collision centrality. The results are compared with the corresponding NA49 data and the measurements from the RHIC BES program.
The elliptic, v2, triangular, v3, and quadrangular, v4, azimuthal anisotropic flow coefficients are measured for unidentified charged particles, pions, and (anti-)protons in Pb–Pb collisions at √sNN=2.76 TeV with the ALICE detector at the Large Hadron Collider. Results obtained with the event plane and four-particle cumulant methods are reported for the pseudo-rapidity range |η|<0.8 at different collision centralities and as a function of transverse momentum, pT, out to pT=20 GeV/c. The observed non-zero elliptic and triangular flow depends only weakly on transverse momentum for pT>8 GeV/c. The small pT dependence of the difference between elliptic flow results obtained from the event plane and four-particle cumulant methods suggests a common origin of flow fluctuations up to pT=8 GeV/c. The magnitude of the (anti-)proton elliptic and triangular flow is larger than that of pions out to at least pT=8 GeV/c indicating that the particle type dependence persists out to high pT.
We report the first results of elliptic (v2), triangular (v3) and quadrangular flow (v4) of charged particles in Pb-Pb collisions at sNN−−−√=5.02 TeV with the ALICE detector at the CERN Large Hadron Collider. The measurements are performed in the central pseudorapidity region |η|<0.8 and for the transverse momentum range 0.2<pT<5 GeV/c. The anisotropic flow is measured using two-particle correlations with a pseudorapidity gap greater than one unit and with the multi-particle cumulant method. Compared to results from Pb-Pb collisions at sNN−−−√=2.76 TeV, the anisotropic flow coefficients v2, v3 and v4 are found to increase by (3.0±0.6)%, (4.3±1.4)% and (10.2±3.8)%, respectively, in the centrality range 0-50%. This increase can be attributed mostly to an increase of the average transverse momentum between the two energies. The measurements are found to be compatible with hydrodynamic model calculations. This comparison provides a unique opportunity to test the validity of the hydrodynamic picture and the power to further discriminate between various possibilities for the temperature dependence of shear viscosity to entropy density ratio of the produced matter in heavy-ion collisions at the highest energies.
We report the first results of elliptic (v2), triangular (v3) and quadrangular flow (v4) of charged particles in Pb-Pb collisions at sNN−−−√=5.02 TeV with the ALICE detector at the CERN Large Hadron Collider. The measurements are performed in the central pseudorapidity region |η|<0.8 and for the transverse momentum range 0.2<pT<5 GeV/c. The anisotropic flow is measured using two-particle correlations with a pseudorapidity gap greater than one unit and with the multi-particle cumulant method. Compared to results from Pb-Pb collisions at sNN−−−√=2.76 TeV, the anisotropic flow coefficients v2, v3 and v4 are found to increase by (3.0±0.6)%, (4.3±1.4)% and (10.2±3.8)%, respectively, in the centrality range 0-50%. This increase can be attributed mostly to an increase of the average transverse momentum between the two energies. The measurements are found to be compatible with hydrodynamic model calculations. This comparison provides a unique opportunity to test the validity of the hydrodynamic picture and the power to further discriminate between various possibilities for the temperature dependence of shear viscosity to entropy density ratio of the produced matter in heavy-ion collisions at the highest energies.
We report the first results of elliptic (v2), triangular (v3) and quadrangular flow (v4) of charged particles in Pb-Pb collisions at sNN−−−√=5.02 TeV with the ALICE detector at the CERN Large Hadron Collider. The measurements are performed in the central pseudorapidity region |η|<0.8 and for the transverse momentum range 0.2<pT<5 GeV/c. The anisotropic flow is measured using two-particle correlations with a pseudorapidity gap greater than one unit and with the multi-particle cumulant method. Compared to results from Pb-Pb collisions at sNN−−−√=2.76 TeV, the anisotropic flow coefficients v2, v3 and v4 are found to increase by (3.0±0.6)%, (4.3±1.4)% and (10.2±3.8)%, respectively, in the centrality range 0-50%. This increase can be attributed mostly to an increase of the average transverse momentum between the two energies. The measurements are found to be compatible with hydrodynamic model calculations. This comparison provides a unique opportunity to test the validity of the hydrodynamic picture and the power to further discriminate between various possibilities for the temperature dependence of shear viscosity to entropy density ratio of the produced matter in heavy-ion collisions at the highest energies.
Measurements of elliptic (v2) and triangular (v3) flow coefficients of π±, K±, p+p¯¯¯, K0S, and Λ+Λ¯¯¯¯ obtained with the scalar product method in Xe-Xe collisions at sNN−−−√ = 5.44 TeV are presented. The results are obtained in the rapidity range |y| < 0.5 and reported as a function of transverse momentum, pT, for several collision centrality classes. The flow coefficients exhibit a particle mass dependence for pT < 3 GeV/c, while a grouping according to particle type (i.e., meson and baryon) is found at intermediate transverse momenta (3 < pT < 8 GeV/c). The magnitude of the baryon v2 is larger than that of mesons up to pT = 6 GeV/c. The centrality dependence of the shape evolution of the pT-differential v2 is studied for the various hadron species. The v2 coefficients of π±, K±, and p+p¯¯¯ are reproduced by MUSIC hydrodynamic calculations coupled to a hadronic cascade model (UrQMD) for pT < 1 GeV/c. A comparison with vn measurements in the corresponding centrality intervals in Pb-Pb collisions at sNN−−−√ = 5.02 TeV yields an enhanced v2 in central collisions and diminished value in semicentral collisions.
Measurements of elliptic (v2) and triangular (v3) flow coefficients of π±, K±, p+p¯¯¯, K0S, and Λ+Λ¯¯¯¯ obtained with the scalar product method in Xe-Xe collisions at sNN−−−√ = 5.44 TeV are presented. The results are obtained in the rapidity range |y|<0.5 and reported as a function of transverse momentum, pT, for several collision centrality classes. The flow coefficients exhibit a particle mass dependence for pT<3 GeV/c, while a grouping according to particle type (i.e., meson and baryon) is found at intermediate transverse momenta (3< pT <8 GeV/c). The magnitude of the baryon v2 is larger than that of mesons up to pT = 6 GeV/c. The centrality dependence of the shape evolution of the pT-differential v2 is studied for the various hadron species. The v2 coefficients of π±, K±, and p+p¯¯¯ are reproduced by MUSIC hydrodynamic calculations coupled to a hadronic cascade model (UrQMD) for pT<1 GeV/c. A comparison with vn measurements in the corresponding centrality intervals in Pb-Pb collisions at sNN−−−√ = 5.02 TeV yields an enhanced v2 in central collisions and diminished value in semicentral collisions.
Measurements of elliptic (v2) and triangular (v3) flow coefficients of π±, K±, p+p¯¯¯, K0S, and Λ+Λ¯¯¯¯ obtained with the scalar product method in Xe-Xe collisions at sNN−−−√ = 5.44 TeV are presented. The results are obtained in the rapidity range |y|<0.5 and reported as a function of transverse momentum, pT, for several collision centrality classes. The flow coefficients exhibit a particle mass dependence for pT<3 GeV/c, while a grouping according to particle type (i.e., meson and baryon) is found at intermediate transverse momenta (3< pT <8 GeV/c). The magnitude of the baryon v2 is larger than that of mesons up to pT = 6 GeV/c. The centrality dependence of the shape evolution of the pT-differential v2 is studied for the various hadron species. The v2 coefficients of π±, K±, and p+p¯¯¯ are reproduced by MUSIC hydrodynamic calculations coupled to a hadronic cascade model (UrQMD) for pT<1 GeV/c. A comparison with vn measurements in the corresponding centrality intervals in Pb-Pb collisions at sNN−−−√ = 5.02 TeV yields an enhanced v2 in central collisions and diminished value in semicentral collisions.
The elliptic (v2), triangular (v3), and quadrangular (v4) flow coefficients of π±, K±, p+p¯¯¯,Λ+Λ¯¯¯¯,K0S, and the ϕ-meson are measured in Pb-Pb collisions at s√NN=5.02 TeV. Results obtained with the scalar product method are reported for the rapidity range |y| < 0.5 as a function of transverse momentum, pT, at different collision centrality intervals between 0–70%, including ultra-central (0–1%) collisions for π±, K±, and p+p¯¯¯. For pT < 3 GeV/c, the flow coefficients exhibit a particle mass dependence. At intermediate transverse momenta (3 < pT < 8–10 GeV/c), particles show an approximate grouping according to their type (i.e., mesons and baryons). The ϕ-meson v2, which tests both particle mass dependence and type scaling, follows p+p¯¯¯ v2 at low pT and π± v2 at intermediate pT. The evolution of the shape of vn(pT) as a function of centrality and harmonic number n is studied for the various particle species. Flow coefficients of π±, K±, and p+p¯¯¯ for pT < 3 GeV/c are compared to iEBE-VISHNU and MUSIC hydrodynamical calculations coupled to a hadronic cascade model (UrQMD). The iEBE-VISHNU calculations describe the results fairly well for pT < 2.5 GeV/c, while MUSIC calculations reproduce the measurements for pT < 1 GeV/c. A comparison to vn coefficients measured in Pb-Pb collisions at sNN−−−√=2.76 TeV is also provided.
The elliptic (v2), triangular (v3), and quadrangular (v4) flow coefficients of π±, K±, p+p¯¯¯, Λ+Λ¯¯¯¯, K0S, and the ϕ-meson are measured in Pb-Pb collisions at sNN−−−√=5.02 TeV. Results obtained with the scalar product method are reported for the rapidity range |y|< 0.5 as a function of transverse momentum, pT, at different collision centrality intervals between 0-70%, including ultra-central (0-1%) collisions for π±, K±, and p+p¯¯¯. For pT<3 GeV/c, the flow coefficients exhibit a particle mass dependence. At intermediate transverse momenta (3<pT<~8-10 GeV/c), particles show an approximate grouping according to their type (i.e., mesons and baryons). The ϕ-meson v2, which tests both particle mass dependence and type scaling, follows p+p¯¯¯ v2 at low pT and π± v2 at intermediate pT. The evolution of the shape of vn(pT) as a function of centrality and harmonic number n is studied for the various particle species. Flow coefficients of π±, K±, and p+p¯¯¯ for pT<3 GeV/c are compared to iEBE-VISHNU and MUSIC hydrodynamical calculations coupled to a hadronic cascade model (UrQMD). The iEBE-VISHNU calculations describe the results fairly well for pT<2.5 GeV/c, while MUSIC calculations reproduce the measurements for pT<1 GeV/c. A comparison to vn coefficients measured in Pb-Pb collisions at sNN−−−√ = 2.76 TeV is also provided.
The elliptic (v2), triangular (v3), and quadrangular (v4) flow coefficients of π±, K±, p+p¯¯¯, Λ+Λ¯¯¯¯, K0S, and the ϕ-meson are measured in Pb-Pb collisions at sNN−−−√=5.02 TeV. Results obtained with the scalar product method are reported for the rapidity range |y|< 0.5 as a function of transverse momentum, pT, at different collision centrality intervals between 0-70%, including ultra-central (0-1%) collisions for π±, K±, and p+p¯¯¯. For pT<3 GeV/c, the flow coefficients exhibit a particle mass dependence. At intermediate transverse momenta (3<pT<~8-10 GeV/c), particles show an approximate grouping according to their type (i.e., mesons and baryons). The ϕ-meson v2, which tests both particle mass dependence and type scaling, follows p+p¯¯¯ v2 at low pT and π± v2 at intermediate pT. The evolution of the shape of vn(pT) as a function of centrality and harmonic number n is studied for the various particle species. Flow coefficients of π±, K±, and p+p¯¯¯ for pT<3 GeV/c are compared to iEBE-VISHNU and MUSIC hydrodynamical calculations coupled to a hadronic cascade model (UrQMD). The iEBE-VISHNU calculations describe the results fairly well for pT<2.5 GeV/c, while MUSIC calculations reproduce the measurements for pT<1 GeV/c. A comparison to vn coefficients measured in Pb-Pb collisions at sNN−−−√ = 2.76 TeV is also provided.
The measurement of two-particle angular correlations is a powerful tool to study jet quenching in a pT region inaccessible by direct jet identification. In these measurements pseudorapidity (Δη) and azimuthal (Δφ) differences are used to extract the shape of the near-side peak formed by particles associated to a higher pT trigger particle (1<pT,trig< 8 GeV/c). A combined fit of the near-side peak and long-range correlations is applied to the data allowing the extraction of the centrality evolution of the peak shape in Pb-Pb collisions at sNN−−−√ = 2.76 TeV. A significant broadening of the peak in the Δη direction at low pT is found from peripheral to central collisions, which vanishes above 4 GeV/c, while in the Δφ direction the peak is almost independent of centrality. For the 10% most central collisions and 1<pT,assoc< 2 GeV/c, 1<pT,trig< 3 GeV/c a novel feature is observed: a depletion develops around the centre of the peak. The results are compared to pp collisions at the same centre of mass energy and to AMPT model simulations. The comparison to the investigated models suggests that the broadening and the development of the depletion is connected to the strength of radial and longitudinal flow.
The measurement of two-particle angular correlations is a powerful tool to study jet quenching in a pT region inaccessible by direct jet identification. In these measurements pseudorapidity (Δη) and azimuthal (Δφ) differences are used to extract the shape of the near-side peak formed by particles associated to a higher pT trigger particle (1<pT,trig< 8 GeV/c). A combined fit of the near-side peak and long-range correlations is applied to the data allowing the extraction of the centrality evolution of the peak shape in Pb-Pb collisions at sNN−−−√ = 2.76 TeV. A significant broadening of the peak in the Δη direction at low pT is found from peripheral to central collisions, which vanishes above 4 GeV/c, while in the Δφ direction the peak is almost independent of centrality. For the 10% most central collisions and 1<pT,assoc< 2 GeV/c, 1<pT,trig< 3 GeV/c a novel feature is observed: a depletion develops around the centre of the peak. The results are compared to pp collisions at the same centre of mass energy and to AMPT model simulations. The comparison to the investigated models suggests that the broadening and the development of the depletion is connected to the strength of radial and longitudinal flow.
The measurement of two-particle angular correlations is a powerful tool to study jet quenching in a pT region inaccessible by direct jet identification. In these measurements pseudorapidity (Δη) and azimuthal (Δφ) differences are used to extract the shape of the near-side peak formed by particles associated to a higher pT trigger particle (1<pT,trig< 8 GeV/c). A combined fit of the near-side peak and long-range correlations is applied to the data allowing the extraction of the centrality evolution of the peak shape in Pb-Pb collisions at sNN−−−√ = 2.76 TeV. A significant broadening of the peak in the Δη direction at low pT is found from peripheral to central collisions, which vanishes above 4 GeV/c, while in the Δφ direction the peak is almost independent of centrality. For the 10% most central collisions and 1<pT,assoc< 2 GeV/c, 1<pT,trig< 3 GeV/c a novel feature is observed: a depletion develops around the centre of the peak. The results are compared to pp collisions at the same centre of mass energy and to AMPT model simulations. The comparison to the investigated models suggests that the broadening and the development of the depletion is connected to the strength of radial and longitudinal flow.
Observations show that, at the beginning of their existence, neutron stars are accelerated briskly to velocities of up to a thousand kilometers per second. We argue that this remarkable effect can be explained as a manifestation of quantum anomalies on astrophysical scales. To theoretically describe the early stage in the life of neutron stars we use hydrodynamics as a systematic effective-field-theory framework. Within this framework, anomalies of the Standard Model of particle physics as underlying microscopic theory imply the presence of a particular set of transport terms, whose form is completely fixed by theoretical consistency. The resulting chiral transport effects in proto-neutron stars enhance neutrino emission along the internal magnetic field, and the recoil can explain the order of magnitude of the observed kick velocities.
The interrelation between quantum anomalies and electromagnetic fields leads to a series of non-dissipative transport effects in QCD. In this work we study anomalous transport phenomena with lattice QCD simulations using improved staggered quarks in the presence of a background magnetic field. In particular, we calculate the conductivities both in the free case and in the interacting case, analysing the dependence of these coefficients with several parameters, such as the temperature and the quark mass.
In dieser Arbeit wird der Strahltransport in einer Niederenergietransportsektion (LEBT) untersucht. Die Untersuchungen werden für die Betriebsmodi der im Aufbau befindlichen Neutronenquelle FRANZ an der Frankfurter Goethe-Universität durchgeführt. Hierbei wird die Akzeptanz eines Choppersystems nach der ersten Sektion des Transportwegs sowie die Akzeptanz des auf die zweite Sektion folgenden RFQ betrachtet und bestmöglich erfüllt. Die Auswirkungen durch die Raumladungswirkung des Ionenstrahls werden berücksichtigt, ebenso die mögliche thermische Belastung durch Strahlverlust an den Komponenten entlang des Strahlwegs. Weiterhin wird der Einfluss eines nicht optimierten Einschusses in den RFQ und die sich daraus ergebenden Strahleigenschaften am Ende des RFQs untersucht.
We present our recent results on antiheavy-antiheavy-light-light tetraquark systems using lattice QCD. Our study of the b¯b¯us four-quark system with quantum numbers JP=1+ and the b¯c¯ud four-quark systems with I(JP)=0(0+) and I(JP)=0(1+) utilizes scattering operators at the sink to improve the extraction of the low-lying energy levels. We found a bound state for b¯b¯us with Ebind,b¯b¯us=(−86±22±10)MeV, but no indication for a bound state in both b¯c¯ud channels. Moreover, we show preliminary results for b¯b¯ud with I(JP)=0(1+), where we used scattering operators both at the sink and the source. We found a bound state and determined its infinite-volume binding energy with a scattering analysis, resulting in Ebind,b¯b¯ud=(−103±8)MeV.
We present our recent results on antiheavy-antiheavy-light-light tetraquark systems using lattice QCD. Our study of the b¯b¯us four-quark system with quantum numbers JP=1+ and the b¯c¯ud four-quark systems with I(JP)=0(0+) and I(JP)=0(1+) utilizes scattering operators at the sink to improve the extraction of the low-lying energy levels. We found a bound state for b¯b¯us with Ebind,b¯b¯us=(−86±22±10)MeV, but no indication for a bound state in both b¯c¯ud channels. Moreover, we show preliminary results for b¯b¯ud with I(JP)=0(1+), where we used scattering operators both at the sink and the source. We found a bound state and determined its infinite-volume binding energy with a scattering analysis, resulting in Ebind,b¯b¯ud=(−103±8)MeV.
We investigate charmonium production in Pb + Pb collisions at LHC beam energy Elab=2.76A TeV at fixed-target experiment (√sNN = 72 GeV). In the frame of a transport approach including cold and hot nuclear matter effects on charmonium evolution, we focus on the antishadowing effect on the nuclear modification factors RAA and rAA for the J/ψ yield and transverse momentum. The yield is more suppressed at less forward rapidity (ylab ≃ 2) than that at very forward rapidity (ylab ≃ 4) due to the shadowing and antishadowing in different rapidity bins.
Es wurde das Leitfähigkeitsverhalten von reinem, lufthaltigem Wasser bei kontinuierlicher und impulsgetasteter Röntgenbestrahlung (60 kV8) untersucht. Hierbei ergaben sich zwei einander überlagerte Effekte: 1. Ein der Röntgen-Dosisleistung proportionaler irreversibler Leitfähigkeitsanstieg, der vermutlich auf eine Strahlenreaktion des gelösten CO2 zurückzuführen ist, 2. eine reversible Leitfähigkeitserhöhung während der Bestrahlung, die sich mit der Entstehung einer Ionenart mit einer mittleren Lebensdauer von ca. 0,15 sec erklären läßt. Es wird angenommen, daß es sich dabei um Radikalionen O2⊖ handelt, welche durch die Reaktion der als Strahlungsprodukt entstehenden Η-Radikale mit dem gelösten Sauerstoff gebildet werden. Ein möglicher chemischer Reaktionsmechanismus wird angegeben, der zu befriedigender quantitativer Übereinstimmung der Versuchsergebnisse mit Ausbeutewerten und Reaktionskonstanten aus der Literatur führt.
One of important consequences of Hagedorn statistical bootstrap model is the prediction of limiting temperature Tcrit for hadron systems colloquially known as Hagedorn temperature. According to Hagedorn, this effect should be observed in hadron spectra obtained in infinite equilibrated nuclear matter rather than in relativistic heavy-ion collisions. We present results of microscopic model calculations for the infinite nuclear matter, simulated by a box with periodic boundary conditions. The limiting temperature indeed appears in the model calculations. Its origin is traced to strings and many-body decays of resonances.
The present research in high energy physics as well as in the nuclear physics requires the use of more powerful and complex particle accelerators to provide high luminosity, high intensity, and high brightness beams to experiments. With the increased technological complexity of accelerators, meeting the demand of experimenters necessitates a blend of accelerator physics with technology. The problem becomes severe when optimization of beam quality has to be provided in accelerator systems with thousands of free parameters including strengths of quadrupoles, sextupoles, RF voltages, etc. Machine learning methods and concepts of artificial intelligence are considered in various industry and scientific branches, and recently, these methods are used in high energy physics mainly for experiments data analysis.
In Accelerator Physics the machine learning approach has not found a wide application yet, and in general the use of these methods is carried out without a deep understanding on their effectiveness with respect to more traditional schemes or other alternative approaches. The purpose of this PhD research is to investigate the methods of machine learning applied to accelerator optimization, accelerator control and in particular on optics measurements and corrections. Optics correction, maximization of acceptance, and simultaneous control of various accelerator components such as focusing magnets is a typical accelerator scenario. The effectiven- ess of machine learning methods in a complex system such as the Large Hadron Collider, which beam dynamics exhibits nonlinear response to machine settings is the core of the study. This work presents successful application of several machine learning techniques such as clustering, decision trees, linear multivariate models and neural networks to beam optics measurements and corrections at the LHC, providing the guidelines for incorporation of machine learning techniques into accelerator operation and discussing future opportunities and potential work in this field.
The search for short-lived particles is usually the final stage in the chain of event reconstruction and precedes event selection when operating in online mode or physics analysis when operating in offline mode. Most often such short-lived particles are neutral and their search and reconstruction is carried out using their daughter charged particles resulting from their decay.
The use of the missing mass method makes it possible to find and analyze also decays of charged short-lived particles, when one of the daughter particles is neutral and is not registered in the detector system. One of the most known examples of such decays is the decay Σ− → nπ−.
In this paper, we discuss in detail the missing mass method, which was implemented as part of the KF Particle Finder package for the search and analysis of short-lived particles, and describe the use of the method in the STAR experiment (BNL, USA).
The method was used to search for pion (π± → μ±ν) and kaon (K± → μ±ν and K± → π±π0) decays online on the HLT farm in the express production chain. An important feature of the express production chain in the STAR experiment is that it allows one to start calibration, production, and analysis of the data immediately after receiving them.
Here, the particular features and results of the real-time application of the method within the express processing of data obtained in the BES-II program at a beam energy of 3.85 GeV/n when working with a fixed target are presented and discussed.
Proteine sind die Maschinen der Zellen. Um die Funktionalität von zahlreichen zellulären Prozessen zu gewährleisten, müssen Kommunikationssignale innerhalb von Proteinen weitergeleitet werden. Die Weiterleitung einer Störung an einem Ort im Protein zu einer entfernten Stelle, an welcher sie strukturelle und/oder dynamische Änderungen auslöst, wird Allosterie genannt. Zunächst wurde Allosterie hauptsächlich mit großräumigen Konformationsänderungen in Verbindung gebracht, aber später entwickelte sich ein dynamischerer Blickwinkel auf Allosterie in Abwesenheit dieser großräumigen Konformationsänderungen. Die Idee eines allosterischen Pfades bestehend aus konservierten und energetisch gekoppelten Aminosäuren, welche die Signalweiterleitung zwischen entfernten Stellen im Protein vermitteln, entstand. Diese allosterischen Pfade wurden durch zahlreiche theoretische Studien in Zusammenhang mit Pfaden effizienten anisotropen Energieflusses gebracht. Der Energiefluss entlang dieser Netzwerke verknüpft allosterische Signalübertragung mit Schwingungsenergietransfer (VET - vibrational energy transfer). Die Großzahl der Forschungsarbeiten über dynamische Allosterie basiert auf theoretischen Methoden, weil nur wenige geeignete experimentelle Verfahren existieren. Um diesen essentiellen biologischen Prozess der Informationsübertragung besser verstehen zu können, ist die Entwicklung neuer und leistungsstarker experimenteller Instrumente und Techniken daher dringend erforderlich. Die vorliegende Dissertation setzt sich dies zum Ziel.
VET in Proteinen ist aufgrund der Proteingeometrie inhärent anisotrop. Alle globulären Proteine besitzen Kanäle effizienten Energieflusses, von denen vermutet wird, dass sie wichtig für Proteinfunktionen, wie die schnelle Ableitung von überschüssiger Wärme, Ligandenbindung und allosterische Signalweiterleitung, sind. VET kann mit zeitaufgelöster Infrarot (IR) Spektroskopie untersucht werden, bei welcher ein Femtosekunden Anregepuls eines Lasers Schwingungsenergie in ein molekulares System an einer bestimmten Stelle injiziert und ein, nach einem veränderbarem Zeitintervall folgender, IR Abfragepuls die Ausbreitung dieser Schwingungsenergie detektiert. Ein protein-kompatibler und universell einsetzbarer Chromophor, der die Energie eines sichtbaren Photons in Schwingungsenergie konvertiert, wird als Heizelement benötigt um langreichweitige VET Pfade in Proteinen kartieren zu können. Der Azulen (Azu) Chromophor eignet sich dafür, weil er nach Photoanregung des ersten elektronischen Zustandes durch ultraschnelle interne Konversion fast die gesamte injizierte Energie innerhalb von einer Picosekunde in Schwingungsenergie umwandelt. Eingebettet in die nicht-kanonische Aminosäure (ncAA - non-canonical amino acid) ß-(1-Azulenyl)-L-Alanine (AzAla), kann der Azu Rest in Proteine eingebaut werden. Die Ankunft der injizierten Schwingungsenergie an einer bestimmten Stelle im Protein kann mithilfe eines IR Sensors detektiert werden. Die Kombination aus Azu als VET Heizelement und Azidohomoalanine (Aha) als VET Sensor mit transienter IR (TRIR) Spektroskopie wurde schon erfolgreich an kleinen Peptiden in der Dissertation von H. M. Müller-Werkmeister getestet, die der vorliegenden Dissertation in den Laboren der Bredenbeck Gruppe vorausging.
Die Schwingungsfrequenz chemischer Bindungen ist hochempfindlich auf selbst kleine Änderungen der Konformation und Dynamik in der unmittelbaren Umgebung und kann mit IR Spektroskopie gemessen werden, z. B. mit Fourier Transform IR (FTIR) Spektroskopie. IR Spektroskopie bietet eine außergewöhnlich gute Zeitauflösung, die es ermöglicht, dynamische Prozesse in Molekülen auf einer Zeitskala von wenigen Picosekunden zu beobachten, wie z. B. die ultraschnelle Weiterleitung von Schwingungsenergie. Mit zweidimensionaler (2D)-IR Spektroskopie können die Relaxation von schwingungsangeregten Zuständen und strukturelle Fluktuationen um die schwingende Bindung untersucht werden. Allerdings geht die herausragende Zeitauflösung mit limitierter spektraler Auflösung einher. In größeren Molekülen mit zahlreichen Bindungen überlagern sich die Schwingungsbanden und die Ortsauflösung geht verloren. Um diese Limitierung zu überwinden, können IR Marker benutzt werden, chemische Gruppen, die in einer spektral durchsichtigen Region des Protein/Wasser Spektrums (1800 bis 2500 cm-1) absorbieren. Als ncAA können sie kotranslational in Proteine an einer gewünschten Stelle eingebaut werden und so ortsspezifische Informationen aus dem Proteininneren liefern. Aufgrund ihrer geringen Größe, eines relativ großen Extinktionskoeffizientens (350-400 M-1cm-1) und einer hohen Empfindlichkeit auf Änderungen in der lokalen Umgebung sind organische Azide (N3) wie zum Beispiel Aha besonders geeignete IR Marker. Aha kann als Methionin Analogon ins Protein eingebaut werden.
...
Approaching the continuum limit of the deconfinement critical point for Nf=2 staggered fermions
(2022)
Quenched QCD at zero baryonic chemical potential undergoes a first-order deconfinement phase transition at a critical temperature Tc, which is related to the spontaneous breaking of the global center symmetry. The center symmetry is broken explicitly by including dynamical quarks, which weaken the first-order phase transition for decreasing quark masses. At a certain critical quark mass, which corresponds to the Z(2)-critical point, the first-order phase transition turns into a smooth crossover. We investigate the Z(2)-critical quark mass for Nf=2 staggered fermions on Nτ=8,10 lattices, where larger Nτ correspond to finer lattices. Monte-Carlo simulations are performed for several quark mass values and aspect ratios in order to extrapolate to the thermodynamic limit. We present final results for Nτ=8 and preliminary results for Nτ=10 for the critical mass, which are obtained from fitting to a kurtosis finite size scaling formula of the absolute value of the Polyakov loop.
We report the first measurement of low-energy proton-capture cross sections of 124Xe in a heavy-ion storage ring. 124Xe54+ ions of five different beam energies between 5.5 and 8 AMeV were stored to collide with a windowless hydrogen target. The 125Cs reaction products were directly detected. The interaction energies are located on the high energy tail of the Gamow window for hot, explosive scenarios such as supernovae and x-ray binaries. The results serve as an important test of predicted astrophysical reaction rates in this mass range. Good agreement in the prediction of the astrophysically important proton width at low energy is found, with only a 30% difference between measurement and theory. Larger deviations are found above the neutron emission threshold, where also neutron and γ widths significantly impact the cross sections. The newly established experimental method is a very powerful tool to investigate nuclear reactions on rare ion beams at low center-of-mass energies.
Abstract: Simple cells in primary visual cortex were famously found to respond to low-level image components such as edges. Sparse coding and independent component analysis (ICA) emerged as the standard computational models for simple cell coding because they linked their receptive fields to the statistics of visual stimuli. However, a salient feature of image statistics, occlusions of image components, is not considered by these models. Here we ask if occlusions have an effect on the predicted shapes of simple cell receptive fields. We use a comparative approach to answer this question and investigate two models for simple cells: a standard linear model and an occlusive model. For both models we simultaneously estimate optimal receptive fields, sparsity and stimulus noise. The two models are identical except for their component superposition assumption. We find the image encoding and receptive fields predicted by the models to differ significantly. While both models predict many Gabor-like fields, the occlusive model predicts a much sparser encoding and high percentages of ‘globular’ receptive fields. This relatively new center-surround type of simple cell response is observed since reverse correlation is used in experimental studies. While high percentages of ‘globular’ fields can be obtained using specific choices of sparsity and overcompleteness in linear sparse coding, no or only low proportions are reported in the vast majority of studies on linear models (including all ICA models). Likewise, for the here investigated linear model and optimal sparsity, only low proportions of ‘globular’ fields are observed. In comparison, the occlusive model robustly infers high proportions and can match the experimentally observed high proportions of ‘globular’ fields well. Our computational study, therefore, suggests that ‘globular’ fields may be evidence for an optimal encoding of visual occlusions in primary visual cortex.
Author Summary: The statistics of our visual world is dominated by occlusions. Almost every image processed by our brain consists of mutually occluding objects, animals and plants. Our visual cortex is optimized through evolution and throughout our lifespan for such stimuli. Yet, the standard computational models of primary visual processing do not consider occlusions. In this study, we ask what effects visual occlusions may have on predicted response properties of simple cells which are the first cortical processing units for images. Our results suggest that recently observed differences between experiments and predictions of the standard simple cell models can be attributed to occlusions. The most significant consequence of occlusions is the prediction of many cells sensitive to center-surround stimuli. Experimentally, large quantities of such cells are observed since new techniques (reverse correlation) are used. Without occlusions, they are only obtained for specific settings and none of the seminal studies (sparse coding, ICA) predicted such fields. In contrast, the new type of response naturally emerges as soon as occlusions are considered. In comparison with recent in vivo experiments we find that occlusive models are consistent with the high percentages of center-surround simple cells observed in macaque monkeys, ferrets and mice.
Ziel der durchgeführten Experimente war es, die Zerfallsmechanismen Van-der-Waals gebundener Argon- und Neon Di- und Trimere in intensiven Laserfeldern zu untersuchen, um mehr über den Einfluss der schwachen Van-der-Waals Bindung auf die Dynamik des Ionisationsprozesses zu erfahren. Da Dimere aufgrund ihrer elektronischen Struktur sehr stark zwei separaten benachbarten Atomen gleichen, vereinen sie atomare und molekulare Eigenschaften in sich und ihre Untersuchung verspricht ein tieferes Verständnis der Wechselwirkungsmechanismen in starken Laserfeldern. Die Verwendung der Impulsspektroskopie Methode COLTRIMS ermöglichte die koinzidente Messung aller beim Aufbruch entstandener ionischer Fragmente sowie eines elektronischen Impulsvektors. Für die beidseitige Einfachionisation des Argon Dimers, konnten bei der gewählten Intensität (etwa 3.3E14W/cm2) drei unterschiedliche Ionisationsprozesse identifiziert werden, von denen zwei zu einer überraschend hohen kinetischen Gesamtenergie der Ionen führen. Aufgrund der Messung der Winkelverteilung der ionischen Fragmente und eines der emittierten Elektronen für lineare und zirkulare Polarisation gelang es, die den drei Prozessen zugrunde liegende Dynamik im Laserfeld zu entschlüsseln. Der dominierende Zerfallskanal stellt demzufolge eine schnelle sequentielle Doppelionisation des Argon Dimers dar, die noch am Gleichgewichtsabstand des Dimers stattfindet. Für den zweithäufigsten Ionisationsprozess ergaben sich zwei mögliche Erklärungsansätze: Entweder wird das Dimer zunächst einseitig doppelionisiert, so dass es auf einer attraktiven Potentialkurve zusammenläuft, bevor es zu einem späteren Zeitpunkt – wenn das Laserfeld bereits abgeklungen ist – durch eine Umverteilung seiner Ladungen in einer Coulomb Explosion fragmentiert, oder das Dimer wird bei einer beidseitigen Tunnelionisation zugleich angeregt, so dass die Coulomb Explosion von einer Potentialkurve erfolgt, die wesentlich steiler als 1/R verläuft. Der schwächste Zerfallskanal, der sich durch die höchste Gesamtenergie auszeichnet, ist auf eine "Frustrated Triple Tunnel Ionization" zurückzuführen, bei der ein hoch angeregter Rydberg Zustand erzeugt wird. Bei der Untersuchung des Neon Dimers konnte bei der gewählten Intensität (etwa 6.3E14W/cm2) nur die sequentielle beidseitige Einfachionisation identifiziert werden, obwohl die Daten Hinweise auf einen weitern Ionisationsprozess mit sehr geringer Statistik aufweisen. Zudem wurde in dieser Arbeit nach der Methode des Coulomb-Explosion-Imaging aus den in Koinzidenz gemessenen Impulsvektoren aller einfachgeladenen ionischen Fragmente eines Aufbruchs die geometrische Struktur der Cluster im Orts-und Impulsraum rekonstruiert. Die ermittelte Grundzustandswellenfunktion des Argon und Neon Dimers zeigt eine gute Übereinstimmung mit quantenmechanischen Berechnungen. Für das Argon und Neon Trimer konnten aus den gemessenen Impulsvektoren mittels einer numerischen Simulation die Bindungswinkel im Ortsraum bestimmt werden, so dass erstmals gezeigt werden konnte, dass diese Trimere gleichseitige Dreieckskonfigurationen aufweisen. Vergleiche mit theoretischen Berechnungen zeigen für die breite Winkelverteilung des Neon Trimers eine hervorragende Übereinstimmung, während die gemessene Winkelverteilung des Argon Trimers etwas breiter als die berechnete ist.
Artificial intelligence in heavy-ion collisions : bridging the gap between theory and experiments
(2023)
Artificial Intelligence (AI) methods are employed to study heavy-ion collisions at intermediate collision energies, where high baryon density and moderate temperature QCD matter is produced. The experimental measurements of various conventional observables such as collective flow, particle number fluctuations, etc. are usually compared with expensive model calculations to infer the physics governing the evolution of the matter produced in the collisions. Various experimental effects and processing algorithms can greatly affect the sensitivity of these observables. AI methods are used to bridge this gap between theory and experiments of heavy-ion collisions. The problems with conventional methods of analyzing experimental data are illustrated in a comparative study of the Glauber MC model and the UrQMD transport model. It is found that the centrality determination and the estimated fluctuations of the number of participant nucleons suffer from strong model dependencies for Au-Au collisions at 1.23 AGeV. This can bias the results of the experimental analysis if the number of participant nucleons used is not consistent throughout the analysis and in the final model-to-data comparison. The measurable consequences of this model dependence of the number of participant nucleons are also discussed. In this context, PointNet-based AI models are developed to accurately reconstruct the impact parameter or the number of participant nucleons in a collision event from the hits and/or reconstructed track of particles in 10 AGeV Au-Au collisions at the CBM experiment. In the last part of the thesis, different AI methods to study the equation of state (EoS) at high baryon densities are discussed. First, a Bayesian inference is performed to constrain the density dependence of the EoS from the available experimental measurements of elliptical flow and mean transverse kinetic energy of mid rapidity protons in intermediate energy collisions. The UrQMD model was augmented to include arbitrary potentials (or equivalently the EoSs) in the QMD part to provide a consistent treatment of the EoS throughout the evolution of the system. The experimental data constrain the posterior constructed for the EoS for densities up to four times saturation density. However, beyond three times saturation density, the shape of the posterior depends on the choice of observables used. There is a tension in the measurements at a collision energy of about 4 GeV. This could indicate large uncertainties in the measurements, or alternatively the inability of the underlying model to describe the observables with a given input EoS. Tighter constraints and fully conclusive statements on the EoS require accurate, high statistics data in the whole beam energy range of 2-10 GeV, which will hopefully be provided by the beam energy scan programme of STAR-FXT at RHIC, the upcoming CBM experiment at FAIR, and future experiments at HIAF and NICA. Finally, it is shown that the PointNet-based models can also be used to identify the equation of state in the CBM experiment. Despite the uncertainties due to limited detector acceptance and biases in the reconstruction algorithms, the PointNet-based models are able to learn the features that can accurately identify the underlying physics of the collision. The PointNet-based models are an ideal AI tool to study heavy-ion collisions, not only to identify the geometric event features, such as the impact parameter or the number of participant nucleons, but also to extract abstract physical features, such as the EoS, directly from the detector outputs.
Nuclear pore complexes (NPCs) mediate nucleocytoplasmic transport. Their intricate 120 MDa architecture remains incompletely understood. Here, we report a near-complete structural model of the human NPC scaffold with explicit membrane and in multiple conformational states. We combined AI-based structure prediction with in situ and in cellulo cryo-electron tomography and integrative modeling. We show that linker Nups spatially organize the scaffold within and across subcomplexes to establish the higher-order structure. Microsecond-long molecular dynamics simulations suggest that the scaffold is not required to stabilize the inner and outer nuclear membrane fusion, but rather widens the central pore. Our work exemplifies how AI-based modeling can be integrated with in situ structural biology to understand subcellular architecture across spatial organization levels.
Landau's Fermi liquid theory has been the main tool for investigating interactions between fermions at low energies for more than 50 years. It has been successful in describing, amongst other things, the mass enhancement in ³He and the thermodynamics of a large class of metals. Whilst this in itself is remarkable given the phenomenological nature of the original theory, experiments have found several materials, such as some superconducting and heavy-fermion materials, which cannot be described within the Fermi liquid picture. Because of this, many attempts have been made to understand these ''non Fermi liquid'' phases from a theoretical perspective. This will be the broad topic of the first part of this thesis and will be investigated in Chapter 2, where we consider a two-dimensional system of electrons interacting close to a Fermi surface through a damped gapless bosonic field. Such systems are known to give rise to non Fermi liquid behaviour. In particular we will consider the Ising-nematic quantum critical point of a two-dimensional metal. At this quantum critical point the Fermi liquid theory breaks down and the fermionic self-energy acquires the non Fermi liquid like {omega}²/³ frequency dependence at lowest order and within the canonical Hertz-Millis approach to quantum criticality of interacting fermions. Previous studies have however shown that, due to the gapless nature of the electronic single-particle excitations, the exponent of 2/3 is modified by an anomalous dimension {eta_psi} which changes, not only the exponent of the frequency dependence, but also the exponent of the momentum dependence of the self-energy. These studies also show that the usual 1/N-expansion breaks down for this problem. We therefore develop an alternative approach to calculate the anomalous dimensions based on the functional renormalization group, which will be introduced in the introductory Chapter 1. Doing so we will be able to calculate both the anomalous dimension renormalizing the exponent of the frequency dependence and the exponent renormalizing the momentum dependence of the self-energy. Moreover we will see that an effective interaction between the bosonic fields, mediated by the fermions, is crucial in order to obtain these renormalizations.
In the second part of this thesis, presented in Chapter 3, we return to Fermi liquid theory itself. Indeed, despite its conceptual simplicity of expressing interacting electrons through long-lived quasi-particles which behave in a similar fashion as free particles, albeit with renormalized parameters, it remains an active area of research. In particular, in order to take into account the full effects of interactions between quasi-particles, it is crucial to consider specific microscopic models. One such effect, which is not captured by the phenomenological theory itself, is the appearance of non-analytic terms in the expansions of various thermodynamic quantities such as heat-capacity and susceptibility with respect to an external magnetic field, temperature, or momentum. Such non-analyticities may have a large impact on the phase diagram of, for example, itinerant electrons near a ferromagnetic quantum phase transition. Inspired by this we consider a system of interacting electrons in a weak external magnetic field within Fermi liquid theory. For this system we calculate various quasi-particle properties such as the quasi-particle residue, momentum-renormalization factor, and a renormalization factor which relates to the self-energy on the Fermi surface. From these renormalization factors we then extract physical quantities such as the renormalized mass and renormalized electron Lande g-factor. By calculating the renormalization factors within second order perturbation theory numerically and analytically, using a phase-space decomposition, we show that all renormalization factors acquire a non-analytic term proportional to the absolute value of the magnetic field. We moreover explicitly calculate the prefactors of these terms and find that they are all universal and determined by low-energy scattering processes which we classify. We also consider the non-analytic contributions to the same renormalization factors at finite temperatures and for finite external frequencies and discuss possible experimental ways of measuring the prefactors. Specifically we find that the tunnelling density of states and the conductivity acquire a non-analytic dependence on magnetic field (and temperature) coming from the momentum-renormalization factor. For the latter we discuss how this relates to previous works which show the existence of non-analyticities in the conductivity at first order in the interaction.
For finite baryon chemical potential, conventional lattice descriptions of quantum chromodynamics (QCD) have a sign problem which prevents straightforward simulations based on importance sampling.
In this thesis we investigate heavy dense QCD by representing lattice QCD with Wilson fermions at finite temperature and density in terms of Polyakov loops.
We discuss the derivation of $3$-dimensional effective Polyakov loop theories from lattice QCD based on a combined strong coupling and hopping parameter expansion, which is valid for heavy quarks.
The finite density sign problem is milder in these theories and they are also amenable to analytic evaluations.
The analytic evaluation of Polyakov loop theories via series expansion techniques is illustrated by using them to evaluate the $\SU{3}$ spin model.
We compute the free energy density to $14$th order in the nearest neighbor coupling and find that predictions for the equation of state agree with simulations to $\mathcal{O}(1\%)$ in the phase were the (approximate) $Z(3)$ center symmetry is intact.
The critical end point is also determined but with less accuracy and our results agree with numerical results to $\mathcal{O}(10\%)$.
While the accuracy for the endpoint is limited for the current length of the series, analytic tools provide valuable insight and are more flexible.
Furthermore they can be generalized to Polyakov-loop-theories with $n$-point interactions.
We also take a detailed look at the hopping expansion for the derivation of the effective theory.
The exponentiation of the action is discussed by using a polymer expansion and we also explain how to obtain logarithmic resummations for all contributions, which will be achieved by employing the finite cluster method know from condensed matter physics.
The finite cluster method can also be used to evaluate the effective theory and comparisons of the evaluation of the effective action and a direction evaluation of the partition function are made.
We observe that terms in the evaluation of the effective theory correspond to partial contractions in the application of Wick's theorem for the evaluation of Grassmann-valued integrals.
Potential problems arising from this fact are explored.
Next to next to leading order results from the hopping expansion are used to analyze and compare the onset transition both for baryon and isospin chemical potential.
Lattice QCD with an isospin chemical potential does not have a sign problem and can serve as a valuable cross-check.
Since we are restricted by the relatively short length of our series, we content ourselves with observing some qualitative phenomenological properties arising in the effective theory which are relevant for the onset transition.
Finally, we generalize our results to arbitrary number of colors $N_c$.
We investigate the transition from a hadron gas to baryon condensation and find that for any finite lattice spacing the transition becomes stronger when $N_c$ is increased and to be first order in the limit of infinite $N_c$.
Beyond the onset, the pressure is shown to scale as $p \sim N_c$ through all available orders in the hopping expansion, which is characteristic for a phase termed quarkyonic matter in the literature.
Some care has to be taken when approaching the continuum, as we find that the continuum limit has to be taken before the large $N_c$ limit.
Although we currently are unable to take the limits in this order, our results are stable in the controlled range of lattice spacings when the limits are approached in this order.
Für das direkte Bild des Schwarzen Lochs benötigten die Astronomen ein Teleskop von bisher unerreichter Präzision und Empfindlichkeit. Das Event-Horizon-Teleskop ist kein einzelnes Teleskop, sondern eine Vernetzung von acht Radioteleskopen auf der ganzen Welt an Standorten mit teilweise herausfordernden klimatischen Bedingungen: auf dem Gipfel des Mauna Kea auf Hawaii, in der Atacama-Wüste in Chile, der Antarktis, in Mexiko, Arizona und der Sierra Nevada in Südspanien. ...
The possible role of a first order QCD phase transition at nonvanishing quark chemical potential and temperature for cold neutron stars and for supernovae is delineated. For cold neutron stars, we use the NJL model with nonvanishing color superconducting pairing gaps, which describes the phase transition to the 2SC and the CFL quark matter phases at high baryon densities. We demonstrate that these two phase transitions can both be present in the core of neutron stars and that they lead to the appearance of a third family of solution for compact stars. In particular, a core of CFL quark matter can be present in stable compact star configurations when slightly adjusting the vacuum pressure to the onset of the chiral phase transition from the hadronic model to the NJL model. We show that a strong first order phase transition can have strong impact on the dynamics of core collapse supernovae. If the QCD phase transition sets in shortly after the first bounce, a second outgoing shock wave can be generated which leads to an explosion. The presence of the QCD phase transition can be read off from the neutrino and antineutrino signal of the supernova.
The anion transport protein of the human erythrocyte membrane, band 3, was solubilized and purified in solutions of the non-ionic detergent nonaethylene glycol lauryl ether and then reconstituted in spherical egg phosphatidylcholine bilayers as described earlier (U. Scheuring, K. Kollewe, W. Haase, and D. Schubert, J. Membrane Biol. 90, 123-135 (1986)). The resulting paucilamellar proteoliposom es of average diameter 70 nm were transformed into smaller vesicles by French press treatment and fractionated according to size by gel filtration. The smallest protein-containing liposomes obtained had diameters around 32 nm; still smaller vesicles were free of protein. All proteoliposome samples studied showed a rapid sulfate efflux which was sensitive to specific inhibitors of band 3-mediated anion exchange. In addition, the orientation of the transport protein in the vesicle membranes was found to be “right-side-out” in all samples. This suggests that the orientation of the protein in the vesicle membranes is dictated by the shape of the protein’s intramembrane domain and that this domain has the form of a truncated cone or pyramid.
Far outside the surface of slabs, the exact exchange (EXX) potential vx falls off as −1/z , if z denotes the direction perpendicular to the surface and the slab is localized around z=0 . Similarly, the EXX energy density ex behaves as −n/(2z) , where n is the electron density. Here, an alternative proof of these relations is given, in which the Coulomb singularity in the EXX energy is treated in a particularly careful fashion. This new approach allows the derivation of the next-to-leading order contributions to the asymptotic vx and ex . It turns out that in both cases, the corrections are proportional to 1/z2 in general.
Atomistic molecular dynamics approach for channeling of charged particles in oriented crystals
(2015)
Der Gitterführungseffekt ist der Prozess der Ausbreitung von geladenen Teilchen entlang der Ebenen oder Achsen von kristallinen Materialien. Seit den 1960er Jahren ist dieser Effekt weitgehend theoretisch und experimentell untersucht worden. Dieser Effekt wurde für die Manipulation von Hochenergiestrahlen, die Hochpräzisionsstruktur- und -fehleranalyse von kristallinen Medien und die Herstellung von hochenergetischer Strahlung angewendet. Zur Abstimmung der Parameter der Gitterführung und Gitterführungsstrahlung wurde dieser Prozess für den Fall von künstlich nanostrukturierten Materialien, wie gebogenen Kristallen, Nanoröhren und Fullerit, angenommen. In den letzten Jahren wurde das Konzept des kristallinen Undulators formuliert und getestet, das besondere Eigenschaften der Strahlung aufgrund der Gitterführung von Projektilen in regelmäßig gebogenen Kristallen vorhersagt.
In dieser Arbeit werden die Prozesse der Gitterführung von Sub- und Multi-GeV-Elektronen und -Positronen durch den atomistischen Molekulardynamik-Ansatz untersucht. Die Ergebnisse dieser Studien wurden in einer Reihe von Artikeln während meiner Promotion in Frankfurt vorgestellt. Dieser Ansatz ermöglicht die Simulation komplexer Fälle von Gitterführung in geraden, gebogenen und periodisch gebogenen Kristallen aus reinen kristallinen Materialien und von gemischten Materialien wie Si-Ge-Kristallen, in mehrschichtigen und nanostrukturierten kristallinen Systemen. Die Arbeit beschreibt die Methode der Simulationen, stellt Ergebnisse von Simulationen für verschiedene Fälle vor und vergleicht die Ergebnisse von Simulationen mit aktuellen experimentellen Daten. Die Ergebnisse werden mit Schätzungen der dechanneling-Länge verglichen, dem Anteil der gittergeführten Projektile, der Winkelverteilung der ausgehenden Projektile und des Strahlungsspektrums.
In Chinese medicine acupuncture points are treated by physical stimuli to counteract various diseases. These stimuli include mechanical stress as applied during the needle manipulation or tuina, high temperatures as applied during moxibustion, and red laser light applied during laser acupuncture. This study aimed to investigate cellular responses to stimuli that might occur in the tissue of acupuncture points. Since they have a characteristically high density of mast cells that degranulate in response to acupuncture, we asked whether these processes lead to ATP release. We tested in in vitro experiments on mast cells of the human mast-cell line HMC-1 the effects of the physical stimuli; mechanical stress was applied by superfusion of the cells with hypotonic solution, heat was applied by incubation of the cells at 52°C, and red laser light of 657 nm was used for irradiation. We demonstrate that all the stimuli induce ATP release from model human mast HMC-1 cells, and this release is associated with an intracellular free Ca2+ rise. We hypothesize that ATP released from mast cells supplements the already known release of ATP from keratinocytes and, by acting on P2X receptors, it may serve as initial mediator of acupuncture-induced analgesia.
Eines der wichtigsten Experimente für Kernstrukturforschung und Messung stellarer Reaktionsraten ist das R3B-Experiment im Rahmen des FAIR-Projekts am GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt. Der experimentelle Aufbau von R3B besteht aus mehreren einzelnen Teilchendetektoren für verschiedene Teilchensorten (Neutronen, Protonen, Spallationsund Spaltprodukte, Gammastrahlen), die alle möglichst vollständig detektiert und gemessen werden müssen. Für die Identifikation und Energiemessung schwerer, geladener Reaktionsprodukte ist eine sogenannte Time-of-Flight-Wall (Flugzeitwand) nötig. Der Name ergibt sich aus der Hauptaufgabe, der Flugzeitmessung für die Energiebestimmung der Teilchen, sowie der Geometrie eines solchen Detektors. Die in vorherigen Aufbauten verwendeten Detektoren diesen Typs erfüllen noch nicht die Anforderungen, die die Forschungsziele des R3B-Experiments stellen, daher wurde ein neues Design basierend auf Plastikszintillatoren entwickelt.
Für diese Arbeit wurde die theoretisch erreichbare Zeitauflösung des neuen Designs abgeschätzt sowie Testmessungen mit verschiedenen experimentellen Setups durchgeführt. Insbesondere wurde ein Prototyp der ToF-Wand im Rahmen einer Strahlzeit an der Beschleunigeranlage der GSI getestet. Die Ergebnisse dieser Messungen mit einem 58Ni28+-Strahl wurden im Hinblick auf Energie-, Zeit- und Ladungsauflösung sowie die Stabilität dieser Werte bei hohen Raten ausgewertet und so ein erster Eindruck von der Leistungsfähigkeit des Detektors und der Ausleseelektronik gewonnen und Einschränkungen und nötige Verbesserungen erkannt.
Neutroneneinfangquerschnitte werden häufig mithilfe der Aktivierungsmethode bestimmt. Hierbei wird die zu untersuchende Probe mit Neutronen der gew¨unschten Energie bestrahlt und danach in einem untergrundoptimierten Labor ausgezählt. Am Institut für Angewandte Physik der Goethe Universität Frankfurt wurde ein solcher Aufbau realisiert. Er besteht aus zwei Clover Detektoren, die gegenüberliegend in enger Geometrie angeordnet sind. Die aktivierte Probe wird mittels spezieller Probenhalter reproduzierbar und zentriert zwischen den Detektoren platziert. Die Clover Detektoren sind mit passiven Schilden (Pb) und einer aktiven Abschirmung (BGO) umgeben. Die unterschiedlichen Abschirmungen wirken sich in verschieden Energiebereichen jeweils anders aus.
Diese Arbeit befasst sich mit der astrophysikalischen Motivation und dem Aufbau, mit dem später die Ausbeute einer neutronenaktivierten Probe bestimmt werden kann. Außerdem werden die Ergebnisse der verschiedenen Untergrundmessungen miteinander verglichen.
In der vorliegenden Arbeit wurden Messungen zur Plasmadynamik eines Lorentz-Drift- Beschleunigers (LDB) durchgeführt. Dieser basiert auf einer koaxialen Elektrodengeometrie. Bei einem Überschlag führt der entstehende Stromfluss zu einemMagnetfeld, sodass die gebildeten Ladungsträger durch die resultierende Lorentzkraft beschleunigt werden. Es hat sich gezeigt, dass die Abhängigkeit von Durchbruchspannung und Druck dem charakteristischen Verlauf einer Paschenkurve folgt.
Die Strom-Spannungs-Charakteristik des Versuchsaufbaus wurde in Konfigurationen mit und ohne Funkenstrecke untersucht. Mit Hilfe von diesem als Schalter fungierenden Spark-Gaps konnte bei Durchbruchspannungen gemessen werden, die oberhalb des Selbstdurchbruchs liegen.
Es zeigte sich, dass die im Versuchaufbau verwendete Funkenstrecke keinen wesentlichen Einfluss auf die Entladung hat. Es kommt an der Funkenstrecke lediglich zu einem Spannungsabfall im Bereich einiger hundert Volt, der den Verlauf derEntladung im LDB allerdings nicht beeinflusst.
Der Lorentz-Drift-Beschleuniger könnte in Zukunft zur Erzeugung eines Druckgradienten verwendet werden, indem Teilchen von einem Rezipienten in einen Zweiten beschleunigt werden. Als Voruntersuchung zur Eingnung dieses als Lorentz-Drift-Ventil bezeichneten Konzeptes wurden Messungen durchgeführt, die den Einfluss der Durchbruchspannung auf die Teilchenbeschleunigung mit Hilfe eines piezokeramischen Elementes untersuchen. So wurde der magnetische Druck bzw. die entsprechende Kraft einer Entladungswolke in Abhängigkeit von Durchbruchspannungen bis etwa 9,5 kV untersucht. Es hat sich gezeigt, dass der Einsatz von hohen Spannungen sinnvoll ist, da sich die auf das Piezoelement einwirkende Kraft quadratisch zur Durchbruchspannung verhält. So wurde die maximale Kraft von 0,44N bei einer Zündspannung von 9,52 kV gemessen.
Zudem wurde untersucht, in welchem Druckbereich der Einfluss der Druckwelle zu messen und wie sich die Geschwindigkeit der Ausbreitung der Druckwelle bei verschiedenen Durchbruchspannungen verhält. Bei einer Entfernung von 231mm zwischen Elektrodengeometrie und Piezoelement hat sich gezeigt, dass im Druckbereich unterhalb von etwa 0,2mbar kein wesentlicher Einfluss des Gasdruckes auf die Piezospannung erkennbar ist. Dies lässt sich durch die geringe Teilchenanzahl im Arbeitsgas begründen, sodass Teilchenstöße vernachlässigt werden können. Die maximale gemessene Geschwindigkeit der durch die Entladung verursachten Druckwelle liegt bei 55 km s ± 10%.
Die gemessene Plasmadynamik lässt darauf schließen, dass das Konzept eines gepulsten Lorentz-Drift-Ventils insbesondere mit hohen Durchbruchspannungen realisierbar ist. Zur Erzeugung eines dauerhaften Druckgradienten müsste die Repetitionsrate allerdings ausreichend hoch sein, sodass der rückfließende Gasdurchsatz geringer ist als die durch den LDB erzeugte Drift. Geht man von der Schallgeschwindigkeit als Rückflussgeschwindigkeit der Teilchen aus, so sind mindestens Repetitionszeiten im Bereich einer Millisekunde erforderlich.
Ergänzend zu den durchgeführten Untersuchungen ist es sinnvoll, die bisherigen Messungen durch Einbau eines Triggers zu verifizieren. Ein Trigger erzeugt eine Vorentladung mit deren Hilfe die eigentliche Entladung auch im Bereich unterhalb des Selbstdurchbruchs gezündet werden kann.
Zunächst sind einige Methoden und Techniken zusammenfassend aufzuzählen, welche mir in meiner Zeit am IKF nahegebracht wurden.
Von technischer Seite her sind hier der Umgang mit der Instituts-eigenen Lichtmikroskop und den pA-Messgeräten sowie der analogen Messkette zu nennen. Außerdem gegebenen GEM-Folien auf Fehlstellen zu untersuchen, sie unter Spannung zu testen und anschließen in die Testkammer zu montieren und diese anschließend ordnungsgemäß in Betrieb zu nehmen. Während des Betriebs der Kammer sind neben den Messungen selbst auch die Programmierung in C++ um ein vorhandenes GUI zu verstehen und erweitern zu können zu nennen. In der Analyse der gewonnenen Daten ist vor allem die im Institut verbreiteten Analyse-Software „Root“ zu nennen um Daten zu verarbeiten, zu plotten und zu fitten.
Der physikalische Gehalt der Messungen war in Folge der ersten Messung nicht mit Sicherheit zu bestimmen, da die Raten-Abhängigkeit des IB entweder grundlegender physikalischer oder technischer Natur sein konnte, was näher zu untersuchen blieb. Nach wiederholter Messung mit größerem Messbereich und einer zweiten Messreihe mit einer anderen Gas-Mischung konnten jedoch Aussagen getroffen werden.
So konnte in der Argon-Messung die gleiche Raten-Abhängigkeit des IBF wie zuvor festgestellt werden, während der IBF in der Neon-Mischung kaum merklich anstieg. Außerdem ist festzuhalten, dass Messungen an der Kathode nur über 10 pA problemlos genau sind. Darunter werden die Werte bei zu wenig Messzeit weniger aussagekräftig.
Ziel der Bachelorarbeit war es, einen Versuch für das Fortgeschrittenen-Praktikum des Instituts für Kernphysik zu konzipieren, der es ermöglicht, die Lebensdauer von aus der kosmischen Strahlung entstandenen Myonen zu bestimmen.
Dazu wurden vorhandene Komponenten auf ihre Gebrauchstauglichkeit getestet und untersucht, insbesondere in Bezug auf die Größe der Szintillatoren, ob der für einen Praktikumsversuch zeitlich gegebene Rahmen eingehalten werden kann.
Es ergaben sich einige mechanische Probleme, insbesondere bei der Verbindung der neuen, größeren Szintillatoren mit den Photomultipliern, die angegangen wurden. Die zuerst getestete Methode stellte sich jedoch als uneffektiv heraus, sodass die endgültige Lösung mit Hilfe einer neuen, computergesteuerten Fräsmaschine der Feinmechanik-Werkstatt erreicht werden soll.
Um die entstandenen Daten zu verarbeiten, wurde ein entsprechendes Programm in LabVIEW entwickelt, das die am TDC abgegriffenen Daten auf ihre Relevanz untersucht und die Ergebnisse in eine Textdatei schreibt. Das LabVIEW Front Panel wurde dabei so gestaltet, dass es den Praktikanten alle wichtigen Daten in graphisch anschaulicher Weise liefert.
Die Daten aus der Textdatei werden dann mit Hilfe eines ROOT Makros mit zwei verschiedenen Exponentialfunktionen gefittet.
In ersten Messungen ergibt sich ein Wert für die Lebensdauer der Myonen, der erstaunlich nahe am Literaturwert liegt.
Die vorliegende Arbeit beschäftigt sich mit der Entwicklung und dem Aufbau eines IHBeschleunigers zur Beschleunigung schwerer Ionen am Brookhaven National Laboratory.
Es wurde eine Einführung in die Arbeit und die Experimente des BNL gegeben, um zu verstehen, welche Aufgabe die IH in Zukunft haben wird und wie diese das BNL in den experimentellen Möglichkeiten erweitert.
Eingebettet in den historischen Kontext wurde zu Beginn die Familie der H-Moden Beschleuniger und ganz besonders die IH erläutert. Wichtige Begriffe und charakteristische Größen, die zum Verständnis der vorliegenden Arbeit nötig sind, wurden eingeführt und deren anschauliche Bedeutung bei der Entwicklung von Beschleunigern klar gemacht.
Eine Neuerung bei der Entwicklung von Driftröhrenbeschleunigern stellt der aufgebaute Messstand und die Computergestützte Datenanalyse dar. Es konnte gezeigt werden, dass die vorgestellte Methodik zur Verarbeitung der Messdaten enorme Verbesserungen mit sich bringt. Daten von unterschiedlichsten Beschleunigern könnern schneller als zuvor analysiert und direkt mit den Sollwerten der Strahldynamik verglichen werden. So kann bereits vor Ort eine mit nur geringen Fehlern behaftete Auswertung erstellt werden und direkt in die weitere Arbeit an einem Beschleuniger mit einfließen.
Die neue Technik wurde im weiteren Verlauf der Arbeit genutzt, um die im Detail eingeführte BNL IH Struktur aufzubauen und für den Einsatz in den USA fertig zu stellen. Neben den exakt auszuführenden Aufbau- und Justierarbeiten wurde viel Zeit in die Erstellung eines ausgereiften Tuningkonzepts investiert. Während dieser Arbeiten wurden die zwar theoretisch bekannten, am Institut aber noch nie nachgewiesenen, parasitären Tunerresonanzen beobachtet. Der zerstörerische Effekt einer solchen Resonanz konnte erstmals gemessen und analysiert werden.
Trotz der üblichen kleineren Schwierigkeiten, die komplexe Projekte mit sich bringen wurde die IH Struktur noch vor Beendigung dieser Arbeit in den USA am BNL aufgestellt und getestet. Es wurde noch nicht die volle Leistung erreicht, aber der Konditionierungsprozess ist in vollem Gange und die vorläufigen Ergebnisse zeigen keine Probleme auf, so dass davon auszugehen ist, dass die IH noch dieses Jahr voll eingesetzt werden kann.
Abschließend kann man sagen, dass das Projekt erfolgreich realisiert wurde und das die Neuerungen aus dieser Arbeit Einzug in weitere Projekte finden werden.
Die vorliegende Arbeit präsentiert den Aufbau und die Diagnostik eines Niederdruck-HF-Plasmas. Durchgeführt wurden die Messungen in einem Gasgemisch aus Ar/He (50%=50%). Sie dienten dazu, nähere Einblicke in die Plasmaparameter eines HF-Plasmas zu erhalten. Einen Schwerpunkt der vorliegenden Arbeit bildete dabei die Auswirkung unterschiedlicher Antennengeometrien auf die Entladungseigenschaften. Hierfür wurden die Plasmaparameter Elektronentemperatur Te, Elektronendichte ne und HF-Leistung in Abhängigkeit des Gasdruckes bei einer Vorwärtsleistung des HF-Generators von 1kW untersucht. Um eine sinnvolle Diagnostik zu gewährleisten, war es zunächst erforderlich eine induktive HF-Einspeisung zu konzipieren und eine Impedanzanpassung an dem vorhandenen 13,56MHz Generator vorzunehmen. Die Einspeisung der HF-Leistung geschieht über eine Spule, nach dem Transformatorprinzip. Der Aufbau bietet die Möglichkeit einer modularen Gestaltung der verwendeten Antennengeometrie. Hierdurch ist es möglich, sowohl die Länge, die Windungsbreite als auch die Windungsanzahl schnell zu ändern, um experimentell ein Optimum der Plasmaparameter bezüglich der Plasmaanregung zu erreichen.
Für die Bestimmung der Plasmaparameter wurde vorwiegend eine nicht invasive Diagnostiktechnik, die Emissionsspektroskopie, eingesetzt. Sie bietet den Vorteil, ein Plasma unberührt zu lassen und dessen Eigenschaften nicht zu verfälschen. Zusätzlich wurde mit einer Langmuirsonde die Elektronendichte gemessen. Die eingespeiste HF-Leistung wurde mit einem im HF-Generator befindlichen Reflektometer überwacht und dokumentiert. Durch systematisch durchgeführte Messungen konnte die Elektronentemperatur in Abhängigkeit des Gasdruckes für unterschiedliche Spulengeometrien mit Hilfe der Spektroskopie bestimmt werden. Es ergaben sich typische Elektronentemperaturen einer induktiven Entladung zwischen 1 eV und 5 eV. Die Ursache einer höheren Elektronentemperatur bei niedrigen Gasdrücken, unterhalb von 1 Pa, kann durch die stochastische Heizung sowie resonante Heizmechanismen erklärt werden.
Die mit der Langmuirsonde bestimmte Elektronendichte belief sich auf 4 x 10 exp 15 m exp -3 bei niedrigen Gasdrücken und einem Maximum von 4 x 10 exp 17 m exp -3 bei einem Gasdruck von 3 Pa. Elektronendichten dieser Größenordnung sind typisch für induktive Entladungsplasmen, die ein Maximum von 1019 m exp -3 [Lie05] erreichen können.
Die eingespeiste HF-Leistung zeigte dabei eine starke Abhängigkeit von der Antennengeometrie. Durch die Optimierung der Spulenkonfiguration ergab sich eine maximale eingespeisten HF-Leistung von 0,8kW.
Ein Vergleich von HF-Leistung und Elektronendichte bestätigte die theoretische Modellvorstellung, die einen linearen Zusammenhang zwischen diesen beiden Größen postuliert. Somit konnten wichtige Eigenschaften bezüglich einer HF-Entladung sowie Einflüsse der Antennengeometrie auf die Entladungseigenschaften untersucht und umfangreich diskutiert werden.
Ziel der vorliegenden Arbeit ist der Aufbau von koaxialen Plasmabeschleunigern und deren Verwendung für die Untersuchung der Eigenschaften von kollidierenden Plasmen. Zukünftig sollen diese kollidierenden Plasmen als intensive Strahlungsquelle im Bereich der ultravioletten (UV-) und vakuumultravioletten (VUV-)Strahlung sowie in der Grundlagenforschung als Target zur Ionenstrahl-Plasma-Wechselwirkung Verwendung finden. Für diese Anwendungen steht dabei eine Betrachtung der physikalischen Grundlagen im Vordergrund. So sind neben der Kenntnis der Plasmadynamik auch Aussagen bezüglich der Elektronendichte, der Elektronentemperatur und der Strahlungsintensität von Bedeutung. Im Einzelnen konnte gezeigt werden, dass es möglich ist, durch eine Plasmakollision die Elektronendichte des Plasmas im Vergleich zu der eines einzelnen Plasmas deutlich zu erhöhen - im Maximalfall um den Faktor vier. Gleichzeitig stieg durch die Plasmakollision die Lichtintensität im Wellenlängenbereich der UV- und VUV-Strahlung um den Faktor drei an...