The production of low mass dielectrons in Au+Au collisions at $\sqrt{s_{NN}}$ = 27 GeV from STAR

20 May 2014, 16:30
2h
spectrum (darmstadtium)

spectrum

darmstadtium

Board: G-12
Poster Electromagnetic Probes Poster session

Speaker

Frank Geurts (Rice University (US))

Description

Dileptons in the low mass region, ($M_{ll} < 1.1 {\rm GeVc}^{-2}$), retain information about vector mesons that originated in the strongly interacting matter created by relativistic heavy-ion collisions. Linking these vector mesons to an in-medium broadening of their spectral functions may suggest chiral symmetry restoration[1]. Measurements at SPS and RHIC energies have been made in the low mass region that are consistent with in-medium modification of the $\rho$ meson spectral function. By using RHIC's beam energy scan (BES) program and its high-purity, large-acceptance electron identification, STAR has been systematically studying the production of low mass dielectrons as a function of collision energy. We present the preliminary results of the low mass dielectron production in Au+Au collisions at $\sqrt{s_{NN}}$ = 27 GeV. The study is focused on the comparison of the spectra with the expected hadronic contributions and with models that include production from $\rho$ with an in-medium modified spectral function and medium radiation. In addition, the results will be compared with previously presented measurements from other BES energies ($\sqrt{s_{NN}}$ = 19.6, 39, and 62.4 GeV) and projections for future BES-2 measurements will be presented. [1] R.Rapp and J.Wambach, Advances in Nuclear Physics 25(2000).
On behalf of collaboration: STAR

Primary authors

Frank Geurts (Rice University (US)) Joey Butterworth (Rice University)

Presentation Materials