Performance studies of the PHENIX Hadron Blind Detector at RHIC

Abstract

Electron pairs or di-leptons in general are unique probes to study the hot and dense matter formed in relativistic heavy ion collisions at RHIC. Particularly, low mass di-leptons are sensitive to chiral symmetry restoration effects and to thermal radiation emitted by the plasma via virtual photons, providing a direct measurement of the quark gluon plasma temperature. But the experimental challenge is the huge combinatorial background created by $e^+e^-$ pairs from copiously produced $\pi^0$ Dalitz decay and $\gamma$ conversions. In order to reduce this background, a Hadron Blind Detector was proposed in PHENIX for electron identification in high-density hadron environment. In the present paper some of the performance studies of the HBD carried with data from 2009 Run are discussed.