Speaker
Leszek Kosarzewski
(Warsaw University of Technology)
Description
Studies of quarkonium production in heavy-ion collisions can provide insight into thermodynamic properties of the quark-gluon plasma (QGP). Suppression of $\Upsilon$ states is expected at a sufficiently high temperature in the QGP and can be measured using the nuclear modification factor $\mbox{$R_{\textit{AA}}$}$. Measurements of $p_{T}$ spectra for separate $\Upsilon$ states in $\mbox{${\it p}+{\it p}$}$ collisions provide constraints for models of the quarkonium production, which is an important factor in the interpretation of the heavy-ion results. In addition, high quality data from $\mbox{${\it p}+{\it p}$}$ collisions at $\mbox{$\sqrt{s}=500\:\mathrm{GeV}$}$ can be used as a baseline for $\mbox{$R_{\textit{AA}}$}$ as a function of $p_{T}$ in $\mbox{${\it Au}+{\it Au}$}$ collisions at $\mbox{$\sqrt{s}=200\:\mathrm{GeV}$}$, after rescaling to lower energy. Also, studies of ratios of $\Upsilon$ states as a function of event multiplicity may help better understand the interactions with hadronic co-movers, because the higher states have larger geometrical sizes and thus should have larger cross section for such interactions compared to $\Upsilon(1S)$.
In this poster, we will focus on experimental aspects and report the preliminary results of $\Upsilon$ measurements in $\mbox{${\it p}+{\it p}$}$ collisions at $\mbox{$\sqrt{s}=500\:\mathrm{GeV}$}$ with the STAR experiment. Furthermore, the prospects of $\Upsilon$ measurements with the newly installed Muon Telescope Detector (MTD) will be discussed.
| On behalf of collaboration: | STAR |
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Primary author
Leszek Kosarzewski
(Warsaw University of Technology)
