Speaker
Prof.
Georg Wolschin
(U Heidelberg)
Description
The suppression of Y mesons in the hot quark-gluon medium (QGP) versus reduced feed-down is investigated in UU collisions at RHIC energies and PbPb collisions at LHC energies. Our centrality- and p_T-dependent model encompasses screening, collisional damping and gluodissociation in the QGP. For Y(1S) it is in agreement with both STAR and CMS data provided the relativistic Doppler effect and the reduced feed-down from the Y(nS) and chi_b(nP) states are properly considered. At both energies, most of the suppression for the Y(1S) state is found to be due to reduced feed-down, whereas most of the Y(2S) suppression is caused by the hot-medium effects. The role of the in-medium effects relative to reduced feed-down increases with energy. The p_T-dependence is flat due to the relativistic Doppler effect. We predict the Y(1S)-suppression in PbPb at sqrt(s_NN) = 5.02 TeV and consider the hot-medium vs. cold nuclear matter (CNM) contribution to the suppression in the asymmetric pPb system at the same energy.
[1] J. Hoelck, F. Nendzig and G. Wolschin, arXiv:1602.00019
Summary
The suppression of Y mesons in the hot quark-gluon medium (QGP) versus reduced feed-down is investigated in UU collisions at RHIC energies and PbPb collisions at LHC energies.
Primary author
Prof.
Georg Wolschin
(U Heidelberg)
