TY  - GEN
A1  - Nendzig, Felix
Y1  - 2014///
TI  - A model for the suppression of Upsilon mesons in PbPb collisions at LHC energies
AV  - public
N2  - A model for the suppression of Upsilon mesons in the quark-gluon plasma (QGP), formed in relativistic PbPb collisions at the LHC, is presented. The model takes the six
bottomium states Y(nS), chi_b(nP) with n = 1,2,3 into account and consists of three steps: First the in-medium wave functions and decay widths are calculated from a non-relativistic, complex potential model. In this approach the following three processes are taken into account: color screening, collisional damping and gluodissociation. In the second step a numerical, hydrodynamical calculation of the
longitudinally and transversely expanding fireball is performed, where the QGP is modeled as a perfect, relativistic fluid. Inserting the results of step one yields QGP suppression factors RAA_QGP, which give for each of the six states the fraction that has survived the fireball. In step three the decay cascade is calculated for the remaining bottomium population for decays within the bottomium family and into dimuon pairs. This yields the final results for the suppression factors RAA of the Y(nS) mesons. It is found that the model is in good agreement with the CMS results for the November 2011 PbPb run for a reasonable choice of parameters. However, the calculated suppression of the excited states Y(2S) and Y(3S) relative to the ground state Y(1S) is not strong enough in this model. Additional mechanisms have to be taken into account to modify the Y(nS)/Y(1S) ratios.
UR  - https://archiv.ub.uni-heidelberg.de/volltextserver/16266/
ID  - heidok16266
ER  -