학술논문

Observation of $D_{s}^{\pm}/D^0$ enhancement in Au+Au collisions at $\sqrt{s_{_{\rm NN}}}$ = 200 GeV
Document Type
article
Source
Subject
hep-ex
Language
Abstract
We report on the first measurement of charm-strange meson $D_s^{\pm}$production at midrapidity in Au+Au collisions at $\sqrt{s_{_{\rm NN}}}$ = 200GeV from the STAR experiment. The yield ratio between strange ($D_{s}^{\pm}$)and non-strange ($D^{0}$) open-charm mesons is presented and compared to modelcalculations. A significant enhancement, relative to a PYTHIA simulation of$p$+$p$ collisions, is observed in the $D_{s}^{\pm}/D^0$ yield ratio in Au+Aucollisions over a large range of collision centralities. Model calculationsincorporating abundant strange-quark production in the quark-gluon plasma (QGP)and coalescence hadronization qualitatively reproduce the data. Thetransverse-momentum integrated yield ratio of $D_{s}^{\pm}/D^0$ at midrapidityis consistent with a prediction from a statistical hadronization model with theparameters constrained by the yields of light and strange hadrons measured atthe same collision energy. These results suggest that the coalescence of charmquarks with strange quarks in the QGP plays an important role in $D_{s}^{\pm}$meson production in heavy-ion collisions.