Dielectron production in Au + Au collisions at sNN =200 GeV

, Mihael Makek, Alexander Milov, Ilia Ravinovich, Deepali Sharma, Sourav Tarafdar, Itzhak Tserruya

פרסום מחקרי: פרסום בכתב עתמאמרביקורת עמיתים

תקציר

We present measurements of e+e- production at midrapidity in Au+Au collisions at sNN=200 GeV. The invariant yield is studied within the PHENIX detector acceptance over a wide range of mass (mee<5 GeV/c2) and pair transverse momentum (pT<5 GeV/c) for minimum bias and for five centrality classes. The e+e- yield is compared to the expectations from known sources. In the low-mass region (mee=0.30-0.76 GeV/c2) there is an enhancement that increases with centrality and is distributed over the entire pair pT range measured. It is significantly smaller than previously reported by the PHENIX experiment and amounts to 2.3±0.4(stat)±0.4(syst)±0.2(model) or to 1.7±0.3(stat)±0.3(syst)±0.2(model) for minimum bias collisions when the open heavy-flavor contribution is calculated with pythia or mc@nlo, respectively. The inclusive mass and pT distributions, as well as the centrality dependence, are well reproduced by model calculations where the enhancement mainly originates from the melting of the ρ meson resonance as the system approaches chiral symmetry restoration. In the intermediate-mass region (mee=1.2-2.8 GeV/c2), the data hint at a significant contribution in addition to the yield from the semileptonic decays of heavy-flavor mesons.

שפה מקוריתאנגלית
מספר המאמר014904
כתב עתPhysical Review C
כרך93
מספר גיליון1
מזהי עצם דיגיטלי (DOIs)
סטטוס פרסוםפורסם - 11 ינו׳ 2016

ASJC Scopus subject areas

  • ???subjectarea.asjc.3100.3106???

טביעת אצבע

להלן מוצגים תחומי המחקר של הפרסום 'Dielectron production in Au + Au collisions at sNN =200 GeV'. יחד הם יוצרים טביעת אצבע ייחודית.

פורמט ציטוט ביבליוגרפי