Speaker
Dr
Yosuke Watanabe
(University of Tokyo)
Description
The measurement of di-electrons is a powerful tool to study the properties of the strongly interacting matter formed in heavy-ion collisions. Since electrons are not subject to final state interactions, they carry the information at the time of their production. In an earlier di-electron measurement by PHENIX[1], a large enhancement of a factor of $\sim$5 with respect to expected hadronic sources was observed in the mass region 0.15-0.75 GeV/$c^2$ for minimum bias events. However, the measurement was limited by a huge combinatorial background dominated by the electrons from $\pi^0$ Dalitz decays and $\gamma$ conversions. In order to remove such background electrons, a Hadron Blind Detector (HBD) was installed as an upgrade of the PHENIX detector. In 2009 and 2010, the HBD was successfully operated and a data sample of p+p collisions and Au+Au collisions were collected. In this presentation, we report the current status of the di-electron analysis at RHIC-PHENIX.
[1] A. Adare et al, Phys. Rev. C81, 034911(2010)
Author
Dr
Yosuke Watanabe
(University of Tokyo)
