Conveners
Parallel Session 4.3: Quarkonia (II)
- Wei Xie (Purdue University (US))
The production of heavy quarkonia is an important observable to study the
properties of the nuclear matter created in high-energy heavy-ion
collisions. Lattice QCD calculations predict a phase transition of the
hadronic matter to a deconfined medium of quarks and gluons, the Quark
Gluon Plasma (QGP), at extreme energy densities. The bottomonium bound
states while passing through the deconfined...
Bottomonia are important probes of the quark-gluon plasma since they are produced at early times and propagate through the medium, mapping its evolution. They are also considered to be cleaner probes than charmonia due to the lack of regeneration even at the LHC energies. In Run 1 at the LHC, CMS was able to explore multiple measurements of the Y(nS) states in pp and PbPb collisions, down to...
The LHCb experiment has the unique property to study heavy-ion interactions in the forward region (2 < $\eta$ < 5), in a kinematic
region complementary to the general purpose detectors. The detector has excellent capabilities for reconstructing quarkonia and open charm states, including baryons, down to zero $p_T$. Notably, it can separate the prompt and displaced charm components. In pPb...
Quarkonium spectral functions have all information about in-medium properties of heavy quarkonia such as dissociation temperatures, which are important to understand suppression of quarkonium yields in relativistic heavy ion collision experiments at RHIC and LHC, where many interesting results on $J/\Psi$ and $\Upsilon$ suppression have been reported already. Since quarkonium suppression can...
Measurements of quarkonium production have played an important role in understanding the properties of the Quark-Gluon Plasma (QGP) formed in relativistic heavy-ion collisions. The suppression of quarkonia in the medium due to color screening has been proposed as a direct signature of the QGP formation. However, other effects, such as regeneration of quarkonia by the coalescence of...
The thermal suppression of heavy quark bound states represents an ideal observable for determining if one has produced a quark gluon plasma in ultrarelativistic heavy-ion collisions. In recent years, however, a paradigm shift has taken place in the theory of quarkonium suppression due to new first principles calculations of the thermal widths of these states. These thermal widths are large, eg...
