Suppression of high $p_{T}$ non-photonic electrons in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV at RHIC.

Jaroslav Bielcik

Strong suppression of high $p_{T}$ hadrons observed at RHIC has led to the interpretation that the energetic partons lose their energy via induced gluon radiation in the hot and dense matter before fragmenting into hadrons. The study of heavy quark production can extend our understanding of this scenario. Due to the dead cone effect, the suppression of heavy quark mesons at high $p_{T}$ is expected to be smaller than that observed for charged hadrons at the same energy. The measurement of non-photonic single electrons up to high $p_{T}$ provides information on charm and beauty production. The semi-leptonic decays of D and B mesons are the dominant contribution to the non-photonic electron spectra. The preliminary spectra from p+p, d+Au and Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV have been extracted for mid-rapidity non-photonic electrons in the range $1.5 < p_{T}$ (GeV/c) $< 10$. The corresponding nuclear modification factors ($R_{AA}$) are presented and show a large suppression in central Au+Au collisions, indicating an unexpectedly large energy loss for heavy quarks in the hot and dense matter created at RHIC. This observed suppression is compared to recent theoretical models.