Search results for "AU COLLISIONS"
showing 10 items of 12 documents
Soft-dielectron excess in proton-proton collisions at $\sqrt{s}$ = 13 TeV
2021
Physical review letters 127(4), 042302 (2021). doi:10.1103/PhysRevLett.127.042302
Measurement of higher cumulants of net-charge multiplicity distributions in Au+Au collisions at √sNN = 7.7-200 GeV
2016
We report the measurement of cumulants (Cn,n = 1,...,4) of the net-charge distributions measured within pseudorapidity (|η| < 0.35) in Au + Au collisions at √sNN = 7.7–200 GeV with the PHENIX experiment at the Relativistic Heavy Ion Collider. The ratios of cumulants (e.g., C1/C2, C3/C1) of the net-charge distributions, which can be related to volume independent susceptibility ratios, are studied as a function of centrality and energy. These quantities are important to understand the quantum-chromodynamics phase diagram and possible existence of a critical end point. The measured values are very well described by expectation from negative binomial distributions. We do not observe any nonmono…
Heavy-flavor electron-muon correlations in p+p and d+Au collisions at sNN−−−−√=200 GeV
2014
Background: Heavy-flavor modification in relativistic p ( d ) + A collisions are sensitive to different kinds of strong-interaction physics ranging from modifications of the nuclear wave function to initial- and final-state energy loss. Modifications to single heavy-flavor particles and their decay leptons at midrapidity and forward rapidity are well established at the Relativistic Heavy Ion Collider (RHIC). Purpose: This paper presents measurements of azimuthal correlations of electron-muon pairs produced from heavy-flavor decays, primarily c ̄ c ,in √ s NN = 200 GeV p + p and d + Au collision using the PHENIX detector at RHIC. The electrons are measured at midrapidity while the muons in t…
ϕ meson production in the forward/backward rapidity region in Cu + Au collisions at √sNN = 200 GeV
2016
The ASY-EOS experiment at GSI: Investigating the symmetry energy at supra-saturation densities
2012
The elliptic-flow ratio of neutrons with respect to protons in reactions of neutron rich heavy-ions systems at intermediate energies has been proposed as an observable sensitive to the strength of the symmetry term in the nuclear Equation Of State (EOS) at supra-saturation densities. The recent results obtained from the existing FOPI/LAND data for $^{197}$Au+$^{197}$Au collisions at 400 MeV/nucleon in comparison with the UrQMD model allowed a first estimate of the symmetry term of the EOS but suffer from a considerable statistical uncertainty. In order to obtain an improved data set for Au+Au collisions and to extend the study to other systems, a new experiment was carried out at the GSI la…
Jet-like correlations with neutral pion triggers in pp and central Pb–Pb collisions at 2.76 TeV
2016
Physics letters / B B763, 238 - 250 (2016). doi:10.1016/j.physletb.2016.10.048
Measurement of dielectron production in central Pb-Pb collisions at √sNN = 2.76 TeV
2019
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. The first measurement of dielectron (e + e −) production in central (0 – 10 %) Pb – Pb collisions at √sNN=2.76TeV at the LHC is presented. The dielectron invariant-mass spectrum is compared to the expected contributions from hadron decays in the invariant-mass range 0 < mee < 3.5 GeV / c2. The ratio of data and the cocktail of hadronic contributions without vacuum ρ0 is measured in the invariant-mass range 0.15 < mee < 0.7 GeV / c2, w…
Measurement of the higher-order anisotropic flow coefficients for identified hadrons in Au + Au collisions at √sNN = 200 GeV
2016
Measurements of the anisotropic flow coefficients v2{2}, v3{3}, v4{4}, and v4{2} for identified particles (π±, K±, and p + p¯) at midrapidity, obtained relative to the event planes m at forward rapidities in Au + Au collisions at √sNN = 200 GeV, are presented as a function of collision centrality and particle transverse momenta pT . The vn coefficients show characteristic patterns consistent with hydrodynamical expansion of the matter produced in the collisions. For each harmonic n, a modified valence quark-number Nq scaling [plotting vn{m}/(Nq ) n/2 versus transverse kinetic energies (KET )/Nq ] is observed to yield a single curve for all the measured particle species for a broad range of …
Centrality-Dependent Modification of Jet-Production Rates in Deuteron-Gold Collisions at √sNN = 200 GeV
2016
Jet production rates are measured in p þ p and d þ Au collisions at √sNN = 200 GeV recorded in 2008 with the PHENIX detector at the Relativistic Heavy Ion Collider. Jets are reconstructed using the R ¼ 0.3 anti-kt algorithm from energy deposits in the electromagnetic calorimeter and charged tracks in multiwire proportional chambers, and the jet transverse momentum (pT ) spectra are corrected for the detector response. Spectra are reported for jets with 12 < pT < 50 GeV=c, within a pseudorapidity acceptance of jηj < 0.3. The nuclear-modification factor (RdAu) values for 0%–100% d þ Au events are found to be consistent with unity, constraining the role of initial state effects on jet product…
Isolated photon production in proton-nucleus collisions at forward rapidity
2018
We calculate isolated photon production at forward rapidities in proton-nucleus collisions in the Color Glass Condensate framework. Our calculation uses dipole cross sections solved from the running coupling Balitsky-Kovchegov equation with an initial condition fit to deep inelastic scattering data. For comparison, we also update the results for the nuclear modification factor for pion production in the same kinematics. We present predictions for future forward RHIC and LHC measurements at $\sqrt{s_{NN}}=200$ GeV and $\sqrt{s_{NN}}=8$ TeV.