Dielectron Mass Spectra fromAu+AuCollisions atsNN=200 GeV

2013/12/31 by STAR Collaboration, J. K. Adkins, L. Adamczyk +384 · 6 citations
Physics and Astronomy · #Collision #Hadron #High-Energy Particle Collisions Research #Invariant mass #Mass spectrum #Particle Detector Development and Performance #Particle physics theoretical and experimental studies #Proton #Spectral function #Spectral line #Yield (engineering) #hep-ex #nucl-ex

paper · pdf · doi:10.1103/physrevlett.113.022301

published as Phys. Rev. Lett. 113, 022301 (2014)

openalex publication_date 2014/07/09 · arxiv created 2014/07/15 · arxiv updated 2014/07/16 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

We report the STAR measurements of dielectron (e⁺e^\ensuremath-) production at midrapidity (|y_ee|<1) in Au+Au collisions at √s_NN=200 GeV. The measurements are evaluated in different invariant mass regions with a focus on 0.30--0.76 (\ensuremathρ-like), 0.76--0.80 (\ensuremathω-like), and 0.98--1.05 (\ensuremathφ-like) GeV/c². The spectrum in the \ensuremathω-like and \ensuremathφ-like regions can be well described by the hadronic cocktail simulation. In the \ensuremathρ-like region, however, the vacuum \ensuremathρ spectral function cannot describe the shape of the dielectron excess. In this range, an enhancement of 1.77\ifmmode±\else\textpm\fi0.11(stat)\ifmmode±\else\textpm\fi0.24(syst)\ifmmode±\else\textpm\fi0.33(cocktail) is determined with respect to the hadronic cocktail simulation that excludes the \ensuremathρ meson. The excess yield in the \ensuremathρ-like region increases with the number of collision participants faster than the \ensuremathω and \ensuremathφ yields. Theoretical models with broadened \ensuremathρ contributions through interactions with constituents in the hot QCD medium provide a consistent description of the dilepton mass spectra for the measurement presented here and the earlier data at the Super Proton Synchrotron energies.

Citations

• Dimuon transverse momentum spectra as a tool to characterize the emission region in heavy-ion collisions
• Comprehensive Interpretation of Thermal Dileptons Measured at the CERN Super Proton Synchrotron
• The STAR time projection chamber: a unique tool for studying high multiplicity events at RHIC
• Evidence for Radial Flow of Thermal Dileptons in High-Energy Nuclear Collisions
• Experimental and theoretical challenges in the search for the quark–gluon plasma: The STAR Collaboration's critical assessment of the evidence from RHIC collisions
• Suppressedπ0Production at Large Transverse Momentum in CentralAu+AuCollisions atsNN=200 GeV

Cited by

• Examinations of the early degrees of freedom in ultrarelativistic nucleus-nucleus collisions
• Photon and dilepton production at the Facility for Proton and Anti-Proton Research and beam-energy scan at the Relativistic Heavy-Ion Collider using coarse-grained microscopic transport simulations
• Nuclear-bound quarkonia and heavy-flavor hadrons
• Heavy-ion collisions at the Large Hadron Collider: A review of the results from Run 1
• Measurements of dielectron production in Au + Au collisions atsNN=200GeV from the STAR experiment
• Beam energy dependence of dielectron production in Au+Au collisions from STAR at RHIC

Related

• Measurements of Dielectron Production in Au+Au Collisions at √s_NN= 27, 39, and 62.4 GeV from the STAR Experiment
• Enhancement of the dielectron continuum in sqrts_NN = 200 GeV Au+Au collisions
• Dielectron production in Au+Au collisions at √s_NN=200 GeV
• Measurement of the dielectron continuum in p+p and Au+Au collisions at RHIC
• Dilepton spectra in p+p and Au+Au collisions at RHIC