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arXiv · 0911.2490

Non Photonic e-D0 correlations in p+p and Au+Au collisions at sqrt(s)NN=200 GeV

Abstract

The sum of charm and beauty in Au+Au collisions at 200 GeV measured through nonphotonic electrons, show similar suppression at high pT as light hadrons, in contrast to expectations based on the dead cone effect. To understand this observation, it is important to separate the charm and beauty components. Non-photonic electron-D0 and electron-hadron azimuthal angular correlations are used to disentangle the contributions from charm and beauty decays. The beauty contribution in p+p collisions at 200 GeV is found to be comparable to charm at pT 5.5 GeV, indicating that beauty may contribute significantly to the non photonic electrons from heavy flavour decays in Au+Au data at high pT. Furthermore, in Au+Au collisions we present the status of D0 meson reconstruction using microvertexing techniques made possible with the addition of the silicon detectors.

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A. Geromitsos, STAR collaboration. 2009-11-12. Non Photonic e-D0 correlations in p+p and Au+Au collisions at sqrt(s)NN=200 GeV. https://doi.org/10.1063/1.3293926

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