Speaker
Dr
Yifei Zhang
(Lawrence Berkeley National Lab)
Description
Heavy quark production in elementary particle collisions are expected to
be calculable in pQCD. In relativistic heavy ion collisions, heavy
quarks are believed to be an ideal probe to study the properties of the
created QCD medium. Early RHIC measurements were carried out mostly via
semi-leptonic decay electrons. There are limitations in the electron
approach: the charm hadron and electron kinematics are only weakly
correlated due to the decay, and measured electrons have mixed
contributions from various charm/bottom hadrons. Thus direct measurement
of charm hadrons via hadronic decays is crucial to better understand
charm-medium interactions at RHIC.
In this talk, we will present the STAR preliminary results of D0 and D*
in year 2009 p+p and D0 in year 2010 Au+Au collisions via hadronic decays
covering $p_T$ from 0.4 to 6 GeV/c in mid-rapidity |y|<1 at
$\sqrt{s_{NN}}$ = 200 GeV. Newly completed full barrel Time-Of-Flight
detector was used in the analysis to improve the daughter hadron
identification. The charm production $p_T$ cross section in p+p
collisions will be compared with pQCD calculations. The nuclear
modification factors as a function of the collision centrality will be
presented to discuss the number of binary collisions scaling of charm
total cross-section. The behavior of D-meson freeze-out properties in
Au+Au collisions will be compared with those of light and multi-strange
hadrons. Preliminary results of the D0 decay vertex reconstruction in
Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV from RHIC year 2007 using the
silicon detectors of the STAR experiment will also be presented.
Primary author
Dr
Yifei Zhang
(Lawrence Berkeley National Lab)
