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arXiv · 1210.8366

Upsilon suppression in PbPb collisions at the LHC

Felix Nendzig·Georg Wolschin
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Abstract

We suggest that the combined effect of screening, gluon-induced dissociation, collisional damping, and reduced feed-down explains most of the sequential suppression of Upsilon(nS) states that has been observed in PbPb relative to pp collisions at sqrt(s_NN) = 2.76 TeV. The suppression is thus a clear, albeit indirect, indication for the presence of a QGP. The Upsilon(1S) ground state suppression is essentially due to reduced feed-down, collisional damping and gluodissociation, whereas screening prevails for the suppression of the excited states.

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Felix Nendzig, Georg Wolschin. 2012-10-31. Upsilon suppression in PbPb collisions at the LHC. https://doi.org/10.1103/physrevc.87.024911

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