Speaker
Description
Measurements of quarkonium production play an important role in understanding the properties of the Quark-Gluon Plasma (QGP) created in relativistic heavy-ion collisions. Quarkonium suppression in the medium due to the color screening effect has been proposed as a direct signature of the QGP formation. However, other effects, such as cold nuclear matter (CNM) effects and regeneration, add additional complications to the interpretation of the observed suppression. Compared to charmonia, bottomonia not only gain less contribution from regeneration due to the smaller b-quark production cross-section, but are also less affected by the CNM effects. Furthermore, different bottomonium states with different binding energies are expected to dissociate at different temperatures, thus measurement of this "sequential melting" can help constrain the thermodynamic properties of the medium.
In this talk, we will present the latest measurements of $\Upsilon$ production in Au+Au collisions at $\sqrt{s_{\scriptsize\mbox{NN}}}$ = 200 GeV via both di-muon and di-electron channels by the STAR experiment. With combination of the data sets taken in 2011, 2014 and 2016, the precision of $\Upsilon$ measurements will be significantly improved compared to previous preliminary results, especially for the excited $\Upsilon$ states. The nuclear modification factors for the ground and excited $\Upsilon$ states will be shown as a function of transverse momentum and centrality, and compared to those measured at the LHC as well as to theoretical calculations.
| Content type | Experiment |
|---|---|
| Collaboration | STAR |
| Centralised submission by Collaboration | Presenter name already specified |
