Refine
Year of publication
Has Fulltext
- yes (1091)
Is part of the Bibliography
- no (1091)
Keywords
- Heavy Ion Experiments (20)
- Hadron-Hadron Scattering (11)
- Hadron-Hadron scattering (experiments) (11)
- LHC (9)
- Heavy-ion collision (6)
- ALICE experiment (4)
- Collective Flow (4)
- Jets (4)
- Quark-Gluon Plasma (4)
- ALICE (3)
- COVID-19 (3)
- Epileptischer Anfall (3)
- Heavy Ions (3)
- Jets and Jet Substructure (3)
- pp collisions (3)
- Beauty production (2)
- Charm physics (2)
- Corona (2)
- Critical care (2)
- Experimental nuclear physics (2)
- Experimental particle physics (2)
- Heavy Quark Production (2)
- Lepton-Nucleon Scattering (experiments) (2)
- Pandemic (2)
- Pandemie (2)
- Particle Correlations and Fluctuations (2)
- Particle and resonance production (2)
- Particle correlations and fluctuations (2)
- Pb–Pb collisions (2)
- Psychiatric disorders (2)
- QCD (2)
- SARS-CoV‑2 (2)
- Seizure (2)
- Single electrons (2)
- Status epilepticus (2)
- 900 GeV (1)
- ALICE detector (1)
- ARDS (1)
- Anti-nuclei (1)
- Boosted Jets (1)
- Cardiopulmonary bypass (1)
- Centrality Class (1)
- Centrality Selection (1)
- Cerebrovascular disorders (1)
- Collective Flow, (1)
- Comparison with QCD (1)
- Covid19-nmr (1)
- Data sharing (1)
- Digitalisierung (1)
- Digitalization (1)
- Electron-pion identification (1)
- Electroweak interaction (1)
- Elliptic flow (1)
- Enteral nutrition (1)
- Epilepsy (1)
- Epileptic seizure (1)
- Femtoscopy (1)
- Fibre/foam sandwich radiator (1)
- Fingolimod (1)
- Genetics (1)
- Germany (1)
- HBT (1)
- Hadron production (1)
- Hadron-Hadron Scattering Heavy (1)
- Hadron-hadron interactions (1)
- Hard Scattering (1)
- Heavy Ion Experiment (1)
- Heavy flavor production (1)
- Heavy flavour production (1)
- Heavy ions (1)
- Heavy-flavour decay muons (1)
- Heavy-flavour production (1)
- Heavy-ion collisions (1)
- High-risk cardiac surgery (1)
- Human behaviour (1)
- Immunogenetics (1)
- Immunology (1)
- Inclusive spectra (1)
- Intensity interferometry (1)
- Invariant Mass Distribution (1)
- Ionisation energy loss (1)
- Jet Physics (1)
- Jet Substructure (1)
- Ländlicher Raum (1)
- Material budget (1)
- Mid-rapidity (1)
- Minimum Bias (1)
- Molecular neuroscience (1)
- Monte Carlo (1)
- Multi-Parton Interactions (1)
- Multi-strange baryons (1)
- Multi-wire proportional drift chamber (1)
- Multiple sclerosis (1)
- NMR spectroscopy (1)
- Neural network (1)
- Neurology (1)
- Nuclear modification factor (1)
- Nutrition risk stratification (1)
- Organ dysfunctions (1)
- Outcome (1)
- PYTHIA (1)
- Particle and Resonance Production (1)
- Pb–Pb (1)
- Personalized medicine (1)
- Pharmaco-nutrition (1)
- Postoperative nutritional management (1)
- Predictive markers (1)
- Production Cross Section (1)
- Prognostic models (1)
- Properties of Hadrons (1)
- Proton–proton (1)
- Quark Deconfinement (1)
- Quark Gluon Plasma (1)
- Quark Production (1)
- Quark gluon plasma (1)
- Quarkonium (1)
- RNA (1)
- Rapidity Range (1)
- Relativistic heavy ion physics (1)
- Relativistic heavy-ion collisions (1)
- Resolution Parameter (1)
- Risk factors (1)
- Rural areas (1)
- SARS-CoV-2 (1)
- Single muons (1)
- Stroke (1)
- Supplemental parenteral nutrition (1)
- Systematic Uncertainty (1)
- Systemic inflammatory response (1)
- TR (1)
- Tele-EEG (1)
- Tele-consultation (1)
- Telekonsil (1)
- Time Projection Chamber (1)
- Tracking (1)
- Transition radiation detector (1)
- Transverse momentum (1)
- Trigger (1)
- Underfeeding (1)
- Vector Boson Production (1)
- Viral infection (1)
- Xenon-based gas mixture (1)
- alteplase (1)
- anaesthesia in orthopaedics (1)
- anaesthetics (1)
- chronic kidney disease (1)
- complication (1)
- dE/dx (1)
- detector (1)
- diabetic nephropathy (1)
- endovascular thrombectomy (1)
- experimental results (1)
- fragment screening (1)
- geriatric medicine (1)
- global change (1)
- habitat destruction (1)
- healthcare systems (1)
- heavy ion experiments (1)
- high-fat-diet (1)
- infection (1)
- inpatient hospital admissions (1)
- land use (1)
- leptin receptor-deficient mouse (1)
- liver (1)
- lockdown (1)
- lungs (1)
- mechanical recanalization (1)
- medical informatics initiative (1)
- metabolomics (1)
- neurocritical care (1)
- pandemic (1)
- prediabetes and type 2 diabetes (1)
- quark gluon plasma (1)
- reduced kidney function (1)
- spectra (1)
- thrombolysis (1)
- university hospitals (1)
- √sN N = 2.76 TeV (1)
Institute
- Physik (1069)
- Frankfurt Institute for Advanced Studies (FIAS) (955)
- Informatik (921)
- Medizin (18)
- Informatik und Mathematik (3)
- Hochschulrechenzentrum (2)
- Biochemie und Chemie (1)
- Biochemie, Chemie und Pharmazie (1)
- Biodiversität und Klima Forschungszentrum (BiK-F) (1)
- Institut für Ökologie, Evolution und Diversität (1)
W±-boson production in p–Pb collisions at √sNN = 8.16 TeV and Pb–Pb collisions at √sNN = 5.02 TeV
(2023)
The production of the W± bosons measured in p–Pb collisions at a centreof-mass energy per nucleon–nucleon collision √sNN = 8.16 TeV and Pb–Pb collisions at √sNN = 5.02 TeV with ALICE at the LHC is presented. The W± bosons are measured via their muonic decay channel, with the muon reconstructed in the pseudorapidity region −4 < ηµ lab < −2.5 with transverse momentum p µ T > 10 GeV/c. While in Pb–Pb collisions the measurements are performed in the forward (2.5 < yµ cms < 4) rapidity region, in p–Pb collisions, where the centre-of-mass frame is boosted with respect to the laboratory frame, the measurements are performed in the backward (−4.46 < yµ cms < −2.96) and forward (2.03 < yµ cms < 3.53) rapidity regions. The W− and W+ production cross sections, leptoncharge asymmetry, and nuclear modification factors are evaluated as a function of the muon rapidity. In order to study the production as a function of the p–Pb collision centrality, the production cross sections of the W− and W+ bosons are combined and normalised to the average number of binary nucleon–nucleon collision hNcolli. In Pb–Pb collisions, the same measurements are presented as a function of the collision centrality. Study of the binary scaling of the W±-boson cross sections in p–Pb and Pb–Pb collisions is also reported. The results are compared with perturbative QCD calculations, with and without nuclear modifications of the Parton Distribution Functions (PDFs), as well as with available data at the LHC. Significant deviations from the theory expectations are found in the two collision systems, indicating that the measurements can provide additional constraints for the determination of nuclear PDFs and in particular of the light-quark distributions.
Direct photon production at mid-rapidity in Pb–Pb collisions at √sNN=2.76 TeV was studied in the transverse momentum range 0.9<pT<14 GeV/c. Photons were detected with the highly segmented electromagnetic calorimeter PHOS and via conversions in the ALICE detector material with the e+e− pair reconstructed in the central tracking system. The results of the two methods were combined and direct photon spectra were measured for the 0–20%, 20–40%, and 40–80% centrality classes. For all three classes, agreement was found with perturbative QCD calculations for pT≳5 GeV/c. Direct photon spectra down to pT≈1 GeV/c could be extracted for the 20–40% and 0–20% centrality classes. The significance of the direct photon signal for 0.9<pT<2.1 GeV/c is 2.6σ for the 0–20% class. The spectrum in this pT range and centrality class can be described by an exponential with an inverse slope parameter of (297±12stat±41syst) MeV. State-of-the-art models for photon production in heavy-ion collisions agree with the data within uncertainties.
A measurement of the transverse momentum spectra of jets in Pb-Pb collisions at sNN−−−√=2.76 TeV is reported. Jets are reconstructed from charged particles using the anti-kT jet algorithm with jet resolution parameters R of 0.2 and 0.3 in pseudo-rapidity |η|<0.5. The transverse momentum pT of charged particles is measured down to 0.15 GeV/c which gives access to the low pT fragments of the jet. Jets found in heavy-ion collisions are corrected event-by-event for average background density and on an inclusive basis (via unfolding) for residual background fluctuations and detector effects. A strong suppression of jet production in central events with respect to peripheral events is observed. The suppression is found to be similar to the suppression of charged hadrons, which suggests that substantial energy is radiated at angles larger than the jet resolution parameter R=0.3 considered in the analysis. The fragmentation bias introduced by selecting jets with a high pT leading particle, which rejects jets with a soft fragmentation pattern, has a similar effect on the jet yield for central and peripheral events. The ratio of jet spectra with R=0.2 and R=0.3 is found to be similar in Pb-Pb and simulated PYTHIA pp events, indicating no strong broadening of the radial jet structure in the reconstructed jets with R<0.3.
The transverse momentum (pT) spectrum and nuclear modification factor (RAA) of reconstructed jets in 0–10% and 10–30% central Pb–Pb collisions at √sNN = 2.76 TeV were measured. Jets were reconstructed using the anti-kT jet algorithm with a resolution parameter of R = 0.2 from charged and neutral particles, utilizing the ALICE tracking detectors and Electromagnetic Calorimeter (EMCal). The jet pT spectra are reported in the pseudorapidity interval of |ηjet| < 0.5 for 40 < pT, jet < 120 GeV/c in 0–10% and for 30 < pT, jet < 100 GeV/c in 10–30% collisions. Reconstructed jets were required to contain a leading charged particle with pT > 5 GeV/c to suppress jets constructed from the combinatorial background in Pb–Pb collisions. The leading charged particle requirement applied to jet spectra both in pp and Pb–Pb collisions had a negligible effect on the RAA. The nuclear modification factor RAA was found to be 0.28 ± 0.04 in 0–10% and 0.35 ± 0.04 in 10–30% collisions, independent of pT, jet within the uncertainties of the measurement. The observed suppression is in fair agreement with expectations from two model calculations with different approaches to jet quenching.
We have performed the first measurement of the coherent ψ(2S) photo production cross section in ultraperipheral Pb–Pb collisions at the LHC. This charmonium excited state is reconstructed via the ψ(2S) → l +l − and ψ(2S) → J/ψπ+π− decays, where the J/ψ decays into two leptons. The analysis is based on an event sample corresponding to an integrated luminosity of about 22 μb−1. The cross section for coherent ψ(2S) production in the rapidity interval −0.9 < y < 0.9 is dσcoh ψ(2S)/dy = 0.83±0.19 stat+syst mb. The ψ(2S) to J/ψ coherent cross section ratio is 0.34+0.08 −0.07(stat + syst). The obtained results are compared to predictions from theoretical models.
A measurement of dijet correlations in p–Pb collisions at √sNN = 5.02 TeV with the ALICE detector is presented. Jets are reconstructed from charged particles measured in the central tracking detectors and neutral energy deposited in the electromagnetic calorimeter. The transverse momentum of the full jet (clustered from charged and neutral constituents) and charged jet (clustered from charged particles only) is corrected event-by-event for the contribution of the underlying event, while corrections for underlying event fluctuations and finite detector resolution are applied on an inclusive basis. A projection of the dijet transverse momentum, kTy = pch+ne T,jet sin(ϕdijet) with ϕdijet the azimuthal angle between a full and charged jet and pch+ne T,jet the transverse momentum of the full jet, is used to study nuclear matter effects in p–Pb collisions. This observable is sensitive to the acoplanarity of dijet production and its potential modification in p–Pb collisions with respect to pp collisions. Measurements of the dijet kTy as a function of the transverse momentum of the full and recoil charged jet, and the event multiplicity are presented. No significant modification of kTy due to nuclear matter effects in p–Pb collisions with respect to the event multiplicity or a PYTHIA8 reference is observed.
The measurement of the mass differences for systems bound by the strong force has reached a very high precision with protons and anti-protons1,2. The extension of such measurement from (anti-)baryons to (anti-)nuclei allows one to probe any difference in the interactions between nucleons and anti-nucleons encoded in the (anti-)nuclei masses. This force is a remnant of the underlying strong interaction among quarks and gluons and can be described by effective theories3, but cannot yet be directly derived from quantum chromodynamics. Here we report a measurement of the difference between the ratios of the mass and charge of deuterons (d) and anti-deuterons (), and 3He and nuclei carried out with the ALICE (A Large Ion Collider Experiment)4 detector in Pb–Pb collisions at a centre-of-mass energy per nucleon pair of 2.76 TeV. Our direct measurement of the mass-over-charge differences confirms CPT invariance to an unprecedented precision in the sector of light nuclei5,6. This fundamental symmetry of nature, which exchanges particles with anti-particles, implies that all physics laws are the same under the simultaneous reversal of charge(s) (charge conjugation C), reflection of spatial coordinates (parity transformation P) and time inversion (T).
We report the first measurement at the LHC of coherent photoproduction of ρ0 mesons in ultra-peripheral Pb-Pb collisions. The invariant mass and transverse momentum distributions for ρ0 production are studied in the π+π− decay channel at mid-rapidity. The production cross section in the rapidity range |y|<0.5 is found to be dσ/dy=425±10(stat.) +42−50(sys.) mb. Coherent ρ0 production is studied with and without requirement of nuclear breakup, and the fractional yields for various breakup scenarios are presented. The results are compared with those from lower energies and with model predictions.
We report the first measurement at the LHC of coherent photoproduction of ρ0 mesons in ultra-peripheral Pb-Pb collisions. The invariant mass and transverse momentum distributions for ρ0 production are studied in the π+π− decay channel at mid-rapidity. The production cross section in the rapidity range |y|<0.5 is found to be dσ/dy=425±10(stat.) +42−50(sys.) mb. Coherent ρ0 production is studied with and without requirement of nuclear breakup, and the fractional yields for various breakup scenarios are presented. The results are compared with those from lower energies and with model predictions based on the Glauber model and the color dipole model. The measured cross section is found to be inconsistent with a scaling of the γ-nucleon cross section using the Glauber model.