Speaker
Bingchu Huang
(STAR BNL)
Description
Ultra-relativistic heavy ion collisions provide a unique environment to study the properties of strongly-coupled Quark Gluon Plasma (sQGP) at high temperature and high energy density. One of the crucial probes to study the sQGP is the di-electron production in the low ($M_{ll}$ $<$ $1.0 GeV/c^{2}$) and the intermediate ($1.0$ $<$ M_{ll}$ $<$ $3 GeV/c^{2}$) mass region. In the intermediate mass region, the di-electron production are directly related to thermal radiation of the sQGP. In the low mass range, we can study the production of vector mesons in the medium, where any modifications observed may relate to the possibility of chiral symmetry restoration. The newly installed STAR Barrel Time-of-Flight detector (TOF) provides high acceptance and efficiency for charged particle identification at mid-rapidity. By combining the time-of-flight from the TOF and the energy loss from Time Projection Chamber, STAR is able to identify electron with high purity from low to intermediate transverse momentum at mid-rapidity.In this talk, we present the measurements of vector meson $\omega$ invariant yields via di-electron decays in 200 GeV p+p and Au+Au collisions and the di-electron continuum spectrum in 200 GeV p+p collisions at mid-rapidity. The perspective on possible comparisons between $\rho\righarrow e^{+} e^{-}$ and $\rho\righarrow pi^{+} pi^{-}$ and limits on $\eta\rightarrow e+e-$ will be discussed.
Primary author
Bingchu Huang
(STAR BNL)
