12-15 April 2016
BNL Physics Building
US/Eastern timezone

$J/\psi$ and $\Upsilon$ measurements via di-lepton decay channels with the STAR experiment

12 Apr 2016, 12:05
Large Seminar Room (BNL Physics Building)

Large Seminar Room

BNL Physics Building


Prof. Rosi Reed (Lehigh University)


Suppression of quarkonia in heavy-ion collisions due to the Debye screening of the potential between the heavy quarks was one of the first hypothesized signatures of the Quark Gluon Plasma (QGP). However, other effects besides Debye screening, such as the statistical recombination of heavy quark anti-quark pairs, or co-mover absorption, can also affect quarkonium production in heavy-ion collisions. The STAR experiment has made many successful measurements of the $J/\psi$ and $\Upsilon$ families via the di-electron channel in p+p, d+Au, Au+Au and U+U collisions, which provide constraints for models of quarkonium production in these various systems. These constraints are necessary to fully understand the influence of the different physics processes on the quarkonium yields. The Muon Telescope Detector (MTD), designed to both trigger on and identify muons based on precise timing information, was fully installed in STAR in 2014. This allows quarkonia measurements via the di-muon channel. In particular, it allows a potential separation of the different $\Upsilon$ states, as muons are much less affected by bremsstrahlung than electrons. In this talk, we present an overview of the measurements of $J/\psi$ and $\Upsilon$ mesons measured by the STAR experiment in both di-electron and di-muon channels. We will highlight the recent measurements of $J/\psi$ suppression and elliptic flow at mid-rapidity in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV down to low transverse momenta. Additionally we will show an outlook towards measuring the $\Upsilon$ in the di-muon channel. We will also present measurements of $\Upsilon$ suppression from both Au+Au and U+U collisions.

Primary author

Prof. Rosi Reed (Lehigh University)

Presentation Materials