camelia mironov
(LLR/Ecole polytechnique)
31/05/12, 16:30
Oral presentation
The Compact Muon Solenoid (CMS) is fully equipped to measure hard probes in the di-muon decay channel in the high multiplicity environment of nucleus-nucleus collisions. Such probes are especially relevant for studying the quark-gluon plasma since they are produced at early times and propagate through the medium, mapping its evolution. CMS has measured the nuclear modification factors of Y(1S)...
Georg Wolschin
(Heidelberg University)
31/05/12, 16:50
Oral presentation
We suggest that gluon-induced dissociation and screening of the Y(nS) states together with feed-down explain the suppression of the Y(2S+3S) states relative to the Y(1S) ground state that has been observed by CMS in PbPb collisions at sqrt(s_NN) = 2.76 TeV at the CERN LHC.
The minimum-bias gluodissociation cross sections of the 1S-3S states are calculated using a screened Cornell potential...
Shawn Whitaker
(Iowa State University)
31/05/12, 17:10
Oral presentation
The suppression of quarkonia in heavy ion collisions has long been thought to provide an indication of the temperature dependent Debye screening length of color charge in the quark gluon plasma. A large sample of d+Au and Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV has been collected by PHENIX in 2008 and 2010. The large statistical sample allows for both the observation of Upsilon in the hot...
Anthony Kesich
(University of California, Davis)
31/05/12, 17:30
Oral presentation
Thermal suppression of quarkonium production in heavy-ion collisions, due to Debye screening of the quark-antiquark potential, has been proposed as a clear signature of quark-gluon plasma (QGP) formation. At RHIC energies, the \$Upsilon meson is a clean probe of the early system thanks to negligible levels of enhancement from b-bbar recombination and non-thermal suppression from co-mover...
Jean-Philippe Lansberg
(IPNO - Paris-Sud U. - CNRS/IN2P3)
31/05/12, 17:50
Oral presentation
In the first part, I will discuss the impact of QCD corrections on the P_T differential cross section for Upsilon production in pp collisions at RHIC, Tevatron and LHC energies, as well as the behaviour of the differential cross section in rapidity. I will discuss the very good agreement between the parameter-free predictions of the Colour-Singlet Model and the first LHC data, especially in...
Che-Ming Ko
(Texas A&M University)
31/05/12, 18:10
Oral presentation
Using the hydrodynamic model to describe the dynamics of heavy ion collisions, we have studied quarkonia production in these collisions by including both their dissociation in initial cold nuclear matter and subsequently produced quark-gluon plasma [1-4]. For the latter, we used the screened Cornell potential and the next-to-leading order perturbative QCD to determine, respectively, their...
