Quark Matter 2015 - XXV International Conference on Ultrarelativistic Nucleus-Nucleus Collisions

Session

Quarkonia IV

30-5

30 Sept 2015, 10:50

Kobe, Fashion Mart, Japan

Conveners

Quarkonia IV

• Blaizot Jean-Paul (CEA (FR))

274. $J/\psi$ and $\Upsilon$ measurements in the di-muon channel in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV with the STAR experiment

Dr Rongrong Ma (Brookhaven National Laboratory)

30/09/2015, 10:50

Quarkonia

Contributed talk

Measurements of quarkonium production in heavy-ion collisions have played an essential role in understanding the properties of the Quark Gluon Plasma (QGP) created in such collisions. In particular, $J/\psi$ suppression in the medium has been proposed as a direct probe of the QGP formation, where quarks and gluons are the relevant degrees of freedom. However, regeneration of $J/\psi$ from...

583. Observation of a J/psi yield enhancement at very low pT in Pb-Pb collisions at 2.76 TeV

Gines Martinez-Garcia (Centre National de la Recherche Scientifique (FR))

30/09/2015, 11:10

Quarkonia

Contributed talk

We report on the first measurement of an excess in the yield of J/psi at very low transverse momentum with respect to expectations from hadronic production, performed by ALICE at the LHC in Pb-Pb collisions at 2.76 TeV. Remarkably, the measured nuclear modification factor of J/$\psi$ in the rapidity range 2.5<$y$<4.0 reaches about 7 (2) for Pb-Pb collisions in the $p_\mathrm{T}$ range...

687. CMS bottomonia results from Run I

Mihee Jo (Centre National de la Recherche Scientifique (FR))

30/09/2015, 11:30

Quarkonia

Contributed talk

Bottomonia are important probes of the quark-gluon plasma since they are produced at early times and propagate through the medium, mapping its evolution. The production cross section of the three Y states (1S, 2S, 3S) was measured separately using the Compact Muon Solenoid (CMS) experimental apparatus, in pp and PbPb collisions at 2.76 TeV. A strong suppression is observed in PbPb collisions,...

71. Upsilon suppression in the QGP at the LHC

Georg Wolschin (Heidelberg University)

30/09/2015, 11:50

Quarkonia

Contributed talk

Heavy quarkonia and in particular, the Upsilon meson as observed by CMS [1] and ALICE [2] have proven to be a very useful tool to investigate the quark-gluon plasma that is likely created in heavy-ion collisions at RHIC and LHC energies. Here it is suggested that the combined effect of gluon-induced dissociation, collisional damping, screening, and reduced feed-down explains [3,4] most of...

711. Dynamical upsilon-suppression in the Schroedinger-Langevin approach

Pol Gossiaux (Subatech)

30/09/2015, 12:10

Quarkonia

Contributed talk

The suppression of upsilon Y(1S) states in AA collisions, observed by the STAR collaboration at RHIC and by the CMS and ALICE collaboration at LHC, is one of the most convincing evidence for the creation of the quark gluon plasma. The precise survival of excited Y(2S) and Y(3S) states vs ground state could even allow to measure the highest temperature reached in those collisions, according for...