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$Upsilon$ production in p+p and Au+Au collisions in STAR

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 نشر من قبل Debasish Das
 تاريخ النشر 2008
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 تأليف Debasish Das




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The study of quarkonium production in relativistic heavy ion collisions provides insight into the properties of the produced medium. The lattice studies show a sequential suppression of quarkonia states when compared to normal nuclear matter; which further affirms that a full spectroscopy including bottomonium can provide us a better thermometer for the matter produced under extreme conditions in relativistic heavy ion collisions. With the completion of the STAR Electromagnetic Calorimeter and with the increased luminosity provided by RHIC in Run 6 and 7, the study of $Upsilon$ production via the di-electron channel becomes possible. We present the results on $Upsilon$ measurements in p+p collisions (from Run 6) along with the first results from Au+Au collisions (in Run 7) at $sqrt{s_{rm{NN}}} = 200$ GeV from the STAR experiment.



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