  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.
