Refine
Year of publication
Document Type
- Article (408)
- Preprint (214)
- Contribution to a Periodical (8)
- Conference Proceeding (6)
- Working Paper (6)
- Book (1)
- Report (1)
Has Fulltext
- yes (644)
Is part of the Bibliography
- no (644)
Keywords
- e +-e − Experiments (12)
- BESIII (11)
- Branching fraction (8)
- Particle and Resonance Production (6)
- Charm Physics (5)
- Spectroscopy (5)
- Heavy-ion collisions (4)
- Lepton colliders (4)
- Quarkonium (4)
- portal hypertension (4)
- stochastic differential utility (4)
- COVID-19 (3)
- Charmed mesons (3)
- Diffraction (3)
- Elastic scattering (3)
- Electroweak interaction (3)
- Exotics (3)
- Hadronic decays (3)
- Polarization (3)
- e+-e− Experiments (3)
- Beam Energy Scan (2)
- Biomarkers (2)
- Branching fractions (2)
- Brassica napus (2)
- COVID-19 surveillance (2)
- Cancer (2)
- Charm physics (2)
- Charmonium (2)
- Chiral Magnetic Effect (2)
- Collectivity (2)
- Correlation (2)
- Electroweak Interaction (2)
- Epidemiology (2)
- FBSDE (2)
- Flavour Physics (2)
- Immunology (2)
- Leptonic, semileptonic & radiative decays (2)
- Mechanisms of disease (2)
- Mitochondria (2)
- Non-small cell lung cancer (2)
- Omicron (2)
- Particle decays (2)
- RHIC (2)
- Radiative decay (2)
- Radiotherapy (2)
- Rare diseases (2)
- Registries (2)
- SARS-CoV-2 (2)
- SARS-CoV-2 monitoring (2)
- STAR (2)
- Shear viscosity (2)
- Treatment (2)
- asset pricing (2)
- cirrhosis (2)
- consumption-portfolio choice (2)
- incomplete markets (2)
- microdosing (2)
- recursive utility (2)
- 140Ce (1)
- 3years (1)
- ACLF (1)
- ADGRE1 (1)
- AIS (1)
- ALK (1)
- ALK-rearranged NSCLC (1)
- ARDS (1)
- ATM (1)
- Acuris (1)
- Acute elbow dislocation (1)
- Advanced biliary tract cancer (1)
- Alpha-synuclein (1)
- Alternative oxidase (1)
- Antibiotic therapy (1)
- Antirheumatic agents (1)
- Araneae (1)
- Artificial Intelligence (1)
- Augenerkrankungen (1)
- Autosomal recessive cutis laxa type 1C (1)
- B-slope (1)
- B.1.1.529 (1)
- BA.4 (1)
- BA.5 (1)
- BESIII detector (1)
- BI1361849 (1)
- BTC (1)
- Bacterial leakage (1)
- Beam energy scan (1)
- Bhabha (1)
- Biodiversity Data (1)
- Biogeography (1)
- Biomedical engineering (1)
- Biomonitoring (1)
- Bipolar disorder (1)
- Born cross section (1)
- Born cross section measurement (1)
- Botanical Collections (1)
- Branching fraction measurement (1)
- CAD/CAM crown (1)
- CAKUT (1)
- CBA (1)
- CEP68 (1)
- COMP (1)
- COVID 19 (1)
- CP violation (1)
- CRVO (1)
- CV9202 (1)
- Cardiac implantable electronic devices (1)
- Cardiac rehabilitation (1)
- Cardiac resynchronization therapy (1)
- Cardiovascular disease risk (1)
- Cardiovascular diseases (1)
- Cement gap (1)
- Charged-particle multiplicity (1)
- Charm quark spatial diffusion coefficient (1)
- Charm vector (1)
- Charmonia (1)
- Charmonium (-like) (1)
- Chest pain unit (1)
- Child (1)
- Chiral magnetic effect (1)
- Circadian (1)
- Cirrhosis (1)
- Classification (1)
- Clinical trial (1)
- Coalescence (1)
- Cognitive impairment (1)
- Cohort studies (1)
- Cold nuclear matter effects (1)
- Colorectal cancer (1)
- Comparative effectiveness research (1)
- Complex II (1)
- Concept paper (1)
- Conometric connection (1)
- Consensus (1)
- Consensus document (1)
- Conservation (1)
- Consumption hump (1)
- Coronary intervention (1)
- Critical care (1)
- Critical point (1)
- Cross section (1)
- D meson (1)
- DME (1)
- DNA-PK (1)
- Dark photon (1)
- Dark sector (1)
- Data Standard (1)
- Data protection (1)
- Data sharing (1)
- Datenschutz (1)
- Dermatomyositis (1)
- Detection workflow (1)
- Deuteron production (1)
- Deutschland (1)
- Di-hadron correlations (1)
- Diagnosis (1)
- Digital (1)
- Digitization (1)
- ECM (1)
- EMR1 (1)
- Ecology (1)
- Ecophysiology (1)
- Ectoparasites (1)
- Education (1)
- Effective form factor (1)
- Einwanderer (1)
- Elastogenesis (1)
- Electromagnetic form factor (1)
- Electromagnetic form factors (1)
- Electromagnetic transitions (1)
- Elliptic flow (1)
- Equity (1)
- Etanercept (1)
- Exercise training (1)
- Experimental nuclear physics (1)
- Experimental particle physics (1)
- Extracellular matrix (1)
- Eye diseases (1)
- EyesiNet (1)
- F4/80 (1)
- FOS: Physical sciences (1)
- Fibulin-4 (1)
- Fibulin-5 (1)
- Flavor changing neutral currents (1)
- Flavor symmetries (1)
- Flow (1)
- Form factors (1)
- Forward physics (1)
- Fracture type (1)
- Fremdbild (1)
- GLM (1)
- Genetics (1)
- Genetics research (1)
- Geschichte 1981-1997 (1)
- Gomphus flavipes (1)
- Groomed jet radius (1)
- HCC (1)
- Hadron-Hadron scattering (experiments) (1)
- Hadronization (1)
- Hand-foot syndrome (1)
- Hantavirus (1)
- Health information (1)
- Health-seeking behaviour (1)
- Heart failure (1)
- Heavy Ion Experiments (1)
- Heavy Quark Production (1)
- Heavy ion collisions (1)
- Heavy-Ion Collision (1)
- Heavy-flavor decay electron (1)
- Heavy-ion (1)
- Helicity amplitude analysis (1)
- Helpline (1)
- Herbaria (1)
- Hif1α (1)
- High Energy Physics - Experiment (hep-ex) (1)
- Higher moments (1)
- Hyperons (1)
- Hypertension (1)
- Hypofractionated radiotherapy (1)
- ICU (1)
- IHMCIF (1)
- IL-6 (1)
- ILUVIEN (1)
- IR (1)
- ISS (1)
- Immunogenetics (1)
- Immunomonitoring (1)
- Implantable cardioverter-defibrillator (1)
- Inclusive branching fraction (1)
- Inflammation (1)
- Initial state radiation (1)
- Integrative Modeling (1)
- Interference fragmentation function (1)
- Invisible decays (1)
- J/ψ suppression (1)
- Jet substructure (1)
- K0S (1)
- K3EDTA plasma sampling (1)
- K48-linked (1)
- K63-linked (1)
- Konzeptpapier (1)
- Landscape ecology (1)
- Landschaftsökologie (1)
- Latent transforming growth factor β-binding protein 4 (1)
- Lehre (1)
- Libellen (1)
- Lifestyle (1)
- Lipidomics (1)
- Liver diseases (1)
- Ltbp-4 (1)
- Ltbp-4L (1)
- Ltbp-4S (1)
- L´evy framework (1)
- MACS (1)
- MCP-1 (1)
- MMPs (1)
- MRSA (1)
- MYCN amplification (1)
- Marginal integrity (1)
- Metabolomics (1)
- Microgap (1)
- Mitochondrial disease (1)
- Models & methods for nuclear reactions (1)
- Molecular diagnostic testing (1)
- Molecular medicine (1)
- Multiple parton interactions (1)
- Multivariate analysis (1)
- Myotis myotis (1)
- NAFLD (1)
- NET (1)
- NMDA IgA/IgM antibodies (1)
- NMDA antibody (1)
- NMR spectroscopy (1)
- NSCLC (1)
- NSTEMI (1)
- Net-charge correlations (1)
- Net-charge fluctuations (1)
- Netzhaut (1)
- Neutrinos (1)
- Neutron physics (1)
- Nonflow (1)
- Nuclear reactions (1)
- Nutzen (1)
- Oncogenes (1)
- Open Access (1)
- Ophiogomphus cecilia (1)
- Orphan disease (1)
- Osteoporosis (1)
- Outcome (1)
- Oxidative phosphorylation (1)
- PBSC (1)
- PDB-Dev (1)
- PDBx/mmCIF (1)
- PDE‐5‐inhibitor (1)
- PDGFRβ (1)
- PI3K (1)
- PRRT (1)
- PTEN (1)
- Pacemaker (1)
- Parkinson disease (1)
- Parkinson’s disease (1)
- Particle and resonance production (1)
- Particle phenomena (1)
- Patient safety (1)
- Periodontal disease (1)
- Periodontal therapy (1)
- Pest-crop interactions (1)
- Phalangeal fractures (1)
- Physical activity (1)
- Plasminogen (1)
- Platelets (1)
- Pneumonia (1)
- Portal veins (1)
- Poverty (1)
- Pre-analytics (1)
- Preclinical research (1)
- Predictive markers (1)
- Prevention (1)
- Prognosis (1)
- Prognostic models (1)
- Prostaglandin (1)
- Proton (1)
- Proton-proton collisions (1)
- Proton–proton collisions (1)
- Psychiatric disorders (1)
- Psychiatry (1)
- Puumala virus (1)
- QCD (1)
- Quantum chromodynamics (1)
- RAS pathway (1)
- RNA (1)
- RNA-binding proteins (1)
- Radiative capture (1)
- Rapps (1)
- Rare decays (1)
- Real world (1)
- Register (1)
- Remission (1)
- Research Infrastructure (1)
- Resonance reactions (1)
- Respiratory chain (1)
- Retina (1)
- Retro-IDEAL (1)
- Rh(II) catalysis (1)
- Rheumatoid arthritis (1)
- Rodent-associated infections (1)
- Roosting place (1)
- SARS CoV 2 (1)
- SD-OCT (1)
- SLC20A1 (1)
- SPSS (1)
- STED superresolution (1)
- Sampling protocol (1)
- Schulbuch (1)
- Schädling (1)
- Seasonal variation (1)
- Seltene Erkrankungen (1)
- Semantics (1)
- Semi-leptonic decays (1)
- Single-molecule biophysics (1)
- Social determinants (1)
- SoftDrop (1)
- Solar insolation (1)
- Sorafenib (1)
- Spatial scales (1)
- Spatio-temporal patterns (1)
- Spin alignment (1)
- Spine care (1)
- Spinturnix myoti (1)
- Splitting function (1)
- Standardization (1)
- Staphylococcus aureus (1)
- Stentoplasty (1)
- Steroid (1)
- Student (1)
- Suicide (1)
- Sunlight (1)
- Super-resolution microscopy (1)
- Surgical oncology (1)
- TACE (1)
- TGR(mREN2)27 (1)
- TP53 mutation status (1)
- Taxonomy (1)
- Techniques Electromagnetic calorimeters (1)
- Telemedicine (1)
- Thermal model (1)
- Thoracic trauma (1)
- Threshold effect (1)
- Thrombosis (1)
- Thromboxane (1)
- Transversity (1)
- UWB diagnostics (1)
- VEGF (1)
- VEGFR-2 (1)
- VEGFR-3 (1)
- Variant of concern (1)
- Veins (1)
- Vertebral augmentation (1)
- Vertebral body stenting (1)
- Vertebral fracture (1)
- Vitreous samples (1)
- Wastewater-based epidemiology (WBE) (1)
- Western diet (1)
- Worldwide Protein Data Bank (1)
- X-ray crystallography (1)
- Y states (1)
- accessory proteins (1)
- acute decompensation (1)
- acute myeloid leukemia (1)
- acute-on-chronic liver failure (1)
- adaptive cardiac remodelling (1)
- adverse events (1)
- alternative oxidase (1)
- anaesthesia in orthopaedics (1)
- anaesthetics (1)
- autoantibodies (1)
- azaindole (1)
- backward stochastic differential equation (1)
- bioactivity testing (1)
- bladder exstrophy-epispadias complex (1)
- bleomycin (1)
- bundle (1)
- c-kit (1)
- capture (1)
- cardiac ischaemia‐reperfusion (1)
- cartilage (1)
- cell stress (1)
- cell-free protein synthesis (1)
- center-of-mass energy (1)
- centrosome (1)
- centrosome linker (1)
- cerium (1)
- certainty equivalents (1)
- charmonium-like states (1)
- cloacal malformation (1)
- complications (1)
- computed tomography (1)
- consumption hump (1)
- convergence (1)
- cross-section (1)
- cytarabine dose (1)
- diabetic macular edema (1)
- diazo compounds (1)
- dimuon (1)
- dynamic programming (1)
- e+e − annihilation (1)
- e+e⁻ − Experiments (1)
- e+e− Experiments (1)
- easyPACId (1)
- ectosomes (1)
- education (1)
- elderly (1)
- electron transport chain (1)
- electron-positron collision (1)
- epigeic spiders (1)
- epigäische Spinnen (1)
- erectile dysfunction (1)
- exosomes (1)
- extracellular vesicles (1)
- fibrogenesis (1)
- fixed point approach (1)
- fluocinolone acetonide (1)
- fluorescent dye (1)
- functional genetics (1)
- generalist predators (1)
- generalistische Prädatoren (1)
- geriatric medicine (1)
- global change (1)
- guidelines (1)
- habit formation (1)
- habitat destruction (1)
- hadron spectroscopy (1)
- hadronic events (1)
- health information exchange (1)
- heavy-ion collisions (1)
- helicity amplitude analysis (1)
- hematotoxicity (1)
- hepatic encephalopathy (1)
- hepatic stellate cells (1)
- hepatocellular cancer (1)
- high-risk neuroblastoma (1)
- immunity (1)
- impatience (1)
- in vitro models (1)
- inclusive J/ψ decays (1)
- inflammation (1)
- intrinsically disordered region (1)
- jumps (1)
- kidney formation (1)
- land use (1)
- leisure (1)
- life-cycle utility maximization (1)
- liver (1)
- liver fibrosis (1)
- mRNA active cancer immunotherapy (1)
- macrophage (1)
- metallo β lactamases (1)
- microparticles (1)
- microvesicles (1)
- microwave ablation (1)
- microwave breast imaging (1)
- minimal information requirements (1)
- mouse (1)
- mouse model (1)
- multiresistant bacteria (1)
- n_TOF (1)
- natural products (1)
- nematophin (1)
- neuroendocrine tumor (1)
- neutralizing antibodies (1)
- neutron (1)
- nonstructural proteins (1)
- non‐selective beta‐blocker (1)
- normalization (1)
- nucleosynthesis (1)
- number of J/ψ events (1)
- optimal investment (1)
- osteoarthritis (1)
- oval split ring resonator (1)
- p+p collisions (1)
- p53 pathway (1)
- patient study (1)
- peptide receptor radionuclide therapy (1)
- peripheral blood stem cell collection (1)
- polyubiquitin (1)
- portosystemic shunt (1)
- prevention (1)
- primary biliary cholangitis (1)
- proteobacteria (1)
- qualitative research (1)
- quality control (1)
- rare diseases (1)
- reactive oxygen species (1)
- renin-angiotensin system (1)
- reproducibility (1)
- resectability (1)
- rigor (1)
- rootletin (1)
- s-process (1)
- second line therapy (1)
- sequential ALK-inhibitor therapy (1)
- simplified production (1)
- sorafenib (1)
- sphingolipid sphingosine-1-phosphate (1)
- sphingolipids (1)
- sphingosine-1-phosphate receptor 5 (1)
- spike protein (1)
- spontaneous portosystemic shunt (1)
- standardization (1)
- steatosis (1)
- stochastic volatility (1)
- structural proteins (1)
- surgery (1)
- systemic sclerosis (1)
- tetraquark (1)
- theranostics (1)
- thiol inhibitors (1)
- thrombospondins (1)
- treatment (1)
- treatment response (1)
- trigger efficiency (1)
- ubiquitin-conjugating enzymes (1)
- urinary tract development (1)
- ursodeoxycholic acid (1)
- variant of concern (1)
- variants of concern (1)
- wage hump (1)
- wastewater-based epidemiology (WBE) (1)
- welfare loss (1)
- wwPDB (1)
- zebrafish development (1)
- Λ+c baryon (1)
- Σ hyperon (1)
- Υ suppression (1)
- ψ(3686) (1)
- fibrogenesis (1)
Institute
- Physik (374)
- Frankfurt Institute for Advanced Studies (FIAS) (106)
- Medizin (91)
- Geowissenschaften (23)
- Präsidium (8)
- Biochemie und Chemie (7)
- Biochemie, Chemie und Pharmazie (7)
- Biowissenschaften (7)
- Wirtschaftswissenschaften (7)
- Center for Financial Studies (CFS) (6)
Data from the first physics run at the Relativistic Heavy-Ion Collider at Brookhaven National Laboratory, Au+Au collisions at sqrt[sNN]=130 GeV, have been analyzed by the STAR Collaboration using three-pion correlations with charged pions to study whether pions are emitted independently at freeze-out. We have made a high-statistics measurement of the three-pion correlation function and calculated the normalized three-particle correlator to obtain a quantitative measurement of the degree of chaoticity of the pion source. It is found that the degree of chaoticity seems to increase with increasing particle multiplicity.
We report high statistics measurements of inclusive charged hadron production in Au+Au and p+p collisions at sqrt[sNN]=200 GeV. A large, approximately constant hadron suppression is observed in central Au+Au collisions for 5<pT<12 GeV/c. The collision energy dependence of the yields and the centrality and pT dependence of the suppression provide stringent constraints on theoretical models of suppression. Models incorporating initial-state gluon saturation or partonic energy loss in dense matter are largely consistent with observations. We observe no evidence of pT-dependent suppression, which may be expected from models incorporating jet attenuation in cold nuclear matter or scattering of fragmentation hadrons.
We report results on rho (770)0--> pi + pi - production at midrapidity in p+p and peripheral Au+Au collisions at sqrt[sNN]=200 GeV. This is the first direct measurement of rho (770)0--> pi + pi - in heavy-ion collisions. The measured rho 0 peak in the invariant mass distribution is shifted by ~40 MeV/c2 in minimum bias p+p interactions and ~70 MeV/c2 in peripheral Au+Au collisions. The rho 0 mass shift is dependent on transverse momentum and multiplicity. The modification of the rho 0 meson mass, width, and shape due to phase space and dynamical effects are discussed.
We present STAR measurements of charged hadron production as a function of centrality in Au+Au collisions at sqrt[sNN ]=130 GeV . The measurements cover a phase space region of 0.2< pT <6.0 GeV/c in transverse momentum and -1< eta <1 in pseudorapidity. Inclusive transverse momentum distributions of charged hadrons in the pseudorapidity region 0.5< | eta | <1 are reported and compared to our previously published results for | eta | <0.5 . No significant difference is seen for inclusive pT distributions of charged hadrons in these two pseudorapidity bins. We measured dN/d eta distributions and truncated mean pT in a region of pT > pcutT , and studied the results in the framework of participant and binary scaling. No clear evidence is observed for participant scaling of charged hadron yield in the measured pT region. The relative importance of hard scattering processes is investigated through binary scaling fraction of particle production.
Transverse energy ( ET ) distributions have been measured for Au+Au collisions at sqrt[sNN ]=200 GeV by the STAR Collaboration at RHIC. ET is constructed from its hadronic and electromagnetic components, which have been measured separately. ET production for the most central collisions is well described by several theoretical models whose common feature is large energy density achieved early in the fireball evolution. The magnitude and centrality dependence of ET per charged particle agrees well with measurements at lower collision energy, indicating that the growth in ET for larger collision energy results from the growth in particle production. The electromagnetic fraction of the total ET is consistent with a final state dominated by mesons and independent of centrality.
We present data on e+ e- pair production accompanied by nuclear breakup in ultraperipheral gold-gold collisions at a center of mass energy of 200 GeV per nucleon pair. The nuclear breakup requirement selects events at small impact parameters, where higher-order diagrams for pair production should be enhanced. We compare the data with two calculations: one based on the equivalent photon approximation, and the other using lowest-order quantum electrodynamics (QED). The data distributions agree with both calculations, except that the pair transverse momentum spectrum disagrees with the equivalent photon approach. We set limits on higher-order contributions to the cross section.
The transverse mass spectra and midrapidity yields for Xi s and Omega s are presented. For the 10% most central collisions, the Xi -bar+/h- ratio increases from the Super Proton Synchrotron to the Relativistic Heavy Ion Collider energies while the Xi -/h- stays approximately constant. A hydrodynamically inspired model fit to the Xi spectra, which assumes a thermalized source, seems to indicate that these multistrange particles experience a significant transverse flow effect, but are emitted when the system is hotter and the flow is smaller than values obtained from a combined fit to pi , K, p, and Lambda s.
The pseudorapidity asymmetry and centrality dependence of charged hadron spectra in d+Au collisions at sqrt[sNN ]=200 GeV are presented. The charged particle density at midrapidity, its pseudorapidity asymmetry, and centrality dependence are reasonably reproduced by a multiphase transport model, by HIJING, and by the latest calculations in a saturation model. Ratios of transverse momentum spectra between backward and forward pseudorapidity are above unity for pT below 5 GeV/c . The ratio of central to peripheral spectra in d+Au collisions shows enhancement at 2< pT <6 GeV/c , with a larger effect at backward rapidity than forward rapidity. Our measurements are in qualitative agreement with gluon saturation and in contrast to calculations based on incoherent multiple partonic scatterings.
The short-lived K(892)* resonance provides an efficient tool to probe properties of the hot and dense medium produced in relativistic heavy-ion collisions. We report measurements of K* in sqrt[sNN]=200GeV Au+Au and p+p collisions reconstructed via its hadronic decay channels K(892)*0-->K pi and K(892)*±-->K0S pi ± using the STAR detector at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. The K*0 mass has been studied as a function of pT in minimum bias p+p and central Au+Au collisions. The K*pT spectra for minimum bias p+p interactions and for Au+Au collisions in different centralities are presented. The K*/K yield ratios for all centralities in Au+Au collisions are found to be significantly lower than the ratio in minimum bias p+p collisions, indicating the importance of hadronic interactions between chemical and kinetic freeze-outs. A significant nonzero K*0 elliptic flow (v2) is observed in Au+Au collisions and is compared to the K0S and Lambda v2. The nuclear modification factor of K* at intermediate pT is similar to that of K0S but different from Lambda . This establishes a baryon-meson effect over a mass effect in the particle production at intermediate pT (2<pT <= 4GeV/c).
Midrapidity open charm spectra from direct reconstruction of D0(D0-bar)-->K± pi ± in d+Au collisions and indirect electron-positron measurements via charm semileptonic decays in p+p and d+Au collisions at sqrt[sNN]=200 GeV are reported. The D0(D0-bar) spectrum covers a transverse momentum (pT) range of 0.1<pT<3 GeV/c, whereas the electron spectra cover a range of 1<pT<4 GeV/c. The electron spectra show approximate binary collision scaling between p+p and d+Au collisions. From these two independent analyses, the differential cross section per nucleon-nucleon binary interaction at midrapidity for open charm production from d+Au collisions at BNL RHIC is d sigma NNcc-bar/dy=0.30±0.04(stat)±0.09(syst) mb. The results are compared to theoretical calculations. Implications for charmonium results in A+A collisions are discussed.
Correlations in the hadron distributions produced in relativistic Au+Au collisions are studied in the discrete wavelet expansion method. The analysis is performed in the space of pseudorapidity (| eta | <= 1) and azimuth(full 2 pi ) in bins of transverse momentum (pt) from 0.14 <= pt <= 2.1GeV/c. In peripheral Au+Au collisions a correlation structure ascribed to minijet fragmentation is observed. It evolves with collision centrality and pt in a way not seen before, which suggests strong dissipation of minijet fragmentation in the longitudinally expanding medium.
Azimuthally sensitive Hanbury Brown-Twiss interferometry in Au+Au collisions at sqrt[sNN]=200 GeV
(2004)
We present the results of a systematic study of the shape of the pion distribution in coordinate space at freeze-out in Au+Au collisions at BNL RHIC using two-pion Hanbury Brown-Twiss (HBT) interferometry. Oscillations of the extracted HBT radii versus emission angle indicate sources elongated perpendicular to the reaction plane. The results indicate that the pressure and expansion time of the collision system are not sufficient to completely quench its initial shape.
The results from the STAR Collaboration on directed flow (v1), elliptic flow (v2), and the fourth harmonic (v4) in the anisotropic azimuthal distribution of particles from Au+Au collisions at sqrt[sNN]=200GeV are summarized and compared with results from other experiments and theoretical models. Results for identified particles are presented and fit with a blast-wave model. Different anisotropic flow analysis methods are compared and nonflow effects are extracted from the data. For v2, scaling with the number of constituent quarks and parton coalescence are discussed. For v4, scaling with v22 and quark coalescence are discussed.
We report inclusive photon measurements about midrapidity ( |y| <0.5 ) from 197 Au + 197 Au collisions at sqrt[sNN ]=130 GeV at RHIC. Photon pair conversions were reconstructed from electron and positron tracks measured with the Time Projection Chamber (TPC) of the STAR experiment. With this method, an energy resolution of Delta E/E ~ 2% at 0.5 GeV has been achieved. Reconstructed photons have also been used to measure the transverse momentum ( pt ) spectra of pi 0 mesons about midrapidity ( |y| <1 ) via the pi 0 --> gamma gamma decay channel. The fractional contribution of the pi 0 --> gamma gamma decay to the inclusive photon spectrum decreases by 20%±5% between pt =1.65 GeV/c and pt =2.4 GeV/c in the most central events, indicating that relative to pi 0 --> gamma gamma decay the contribution of other photon sources is substantially increasing.
We report on the rapidity and centrality dependence of proton and antiproton transverse mass distributions from 197Au + 197Au collisions at sqrt[sNN ]=130 GeV as measured by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). Our results are from the rapidity and transverse momentum range of |y| <0.5 and 0.35< pt <1.00 GeV/c . For both protons and antiprotons, transverse mass distributions become more convex from peripheral to central collisions demonstrating characteristics of collective expansion. The measured rapidity distributions and the mean transverse momenta versus rapidity are flat within |y| <0.5 . Comparisons of our data with results from model calculations indicate that in order to obtain a consistent picture of the proton (antiproton) yields and transverse mass distributions the possibility of prehadronic collective expansion may have to be taken into account.
We present the first large-acceptance measurement of event-wise mean transverse momentum <pt> fluctuations for Au-Au collisions at nucleon-nucleon center-of-momentum collision energy sqrt[sNN] = 130 GeV. The observed nonstatistical <pt> fluctuations substantially exceed in magnitude fluctuations expected from the finite number of particles produced in a typical collision. The r.m.s. fractional width excess of the event-wise <pt> distribution is 13.7±0.1(stat) ±1.3(syst)% relative to a statistical reference, for the 15% most-central collisions and for charged hadrons within pseudorapidity range | eta |<1,2 pi azimuth, and 0.15 <= pt <= 2 GeV/c. The width excess varies smoothly but nonmonotonically with collision centrality and does not display rapid changes with centrality which might indicate the presence of critical fluctuations. The reported <pt> fluctuation excess is qualitatively larger than those observed at lower energies and differs markedly from theoretical expectations. Contributions to <pt> fluctuations from semihard parton scattering in the initial state and dissipation in the bulk colored medium are discussed.
We present STAR measurements of the azimuthal anisotropy parameter v2 and the binary-collision scaled centrality ratio RCP for kaons and lambdas ( Lambda + Lambda -bar) at midrapidity in Au+Au collisions at sqrt[sNN]=200 GeV. In combination, the v2 and RCP particle-type dependencies contradict expectations from partonic energy loss followed by standard fragmentation in vacuum. We establish pT ~ 5 GeV/c as the value where the centrality dependent baryon enhancement ends. The K0S and Lambda + Lambda -bar v2 values are consistent with expectations of constituent-quark-number scaling from models of hadron formation by parton coalescence or recombination.
Pion-kaon correlation functions are constructed from central Au+Au STAR data taken at sqrt[sNN]=130 GeV by the STAR detector at the Relativistic Heavy Ion Collider (RHIC). The results suggest that pions and kaons are not emitted at the same average space-time point. Space-momentum correlations, i.e., transverse flow, lead to a space-time emission asymmetry of pions and kaons that is consistent with the data. This result provides new independent evidence that the system created at RHIC undergoes a collective transverse expansion.
We report measurements of single-particle inclusive spectra and two-particle azimuthal distributions of charged hadrons at high transverse momentum (high pT) in minimum bias and central d+Au collisions at sqrt[sNN]=200 GeV. The inclusive yield is enhanced in d+Au collisions relative to binary-scaled p+p collisions, while the two-particle azimuthal distributions are very similar to those observed in p+p collisions. These results demonstrate that the strong suppression of the inclusive yield and back-to-back correlations at high pT previously observed in central Au+Au collisions are due to final-state interactions with the dense medium generated in such collisions.
Transverse mass and rapidity distributions for charged pions, charged kaons, protons, and antiprotons are reported for sqrt[sNN]=200 GeV pp and Au+Au collisions at Relativistic Heary Ion Collider (RHIC). Chemical and kinetic equilibrium model fits to our data reveal strong radial flow and long duration from chemical to kinetic freeze-out in central Au+Au collisions. The chemical freeze-out temperature appears to be independent of initial conditions at RHIC energies.