Upsilon production in p-Pb interactions is studied at the centre-of-mass energy per nucleon-nucleon collision root s = 8.16 TeV with the ALICE detector at the CERN LHC. The measurement is performed reconstructing bottomonium resonances via their dimuon decay channel, in the centre-of-mass rapidity intervals 2.03 < 3.53 and -4.46 y -2.96, down to zero transverse momentum. In this work, results on the Upsilon(1S) production cross section as a function of rapidity and transverse momentum are presented. The corresponding nuclear modification factor shows a suppression of the Upsilon(1S) yields with respect to pp collisions, both at forward and backward rapidity. This suppression is stronger in the low transverse momentum region and shows no significant dependence on the centrality of the interactions. Furthermore, the Upsilon(2S) nuclear modification factor is evaluated, suggesting a suppression similar to that of the Upsilon(1S). A first measurement of the Upsilon(3S) has also been performed. Finally, results are compared with previous ALICE measurements in p-Pb collisions at root s= 5.02 TeV and with theoretical calculations. (C) 2020 European Organization for Nuclear Research. Published by Elsevier B.V.
ϒ production in p–Pb collisions at sNN=8.16 TeV
Mastroserio, A.;
2020-01-01
Abstract
Upsilon production in p-Pb interactions is studied at the centre-of-mass energy per nucleon-nucleon collision root s = 8.16 TeV with the ALICE detector at the CERN LHC. The measurement is performed reconstructing bottomonium resonances via their dimuon decay channel, in the centre-of-mass rapidity intervals 2.03 < 3.53 and -4.46 y -2.96, down to zero transverse momentum. In this work, results on the Upsilon(1S) production cross section as a function of rapidity and transverse momentum are presented. The corresponding nuclear modification factor shows a suppression of the Upsilon(1S) yields with respect to pp collisions, both at forward and backward rapidity. This suppression is stronger in the low transverse momentum region and shows no significant dependence on the centrality of the interactions. Furthermore, the Upsilon(2S) nuclear modification factor is evaluated, suggesting a suppression similar to that of the Upsilon(1S). A first measurement of the Upsilon(3S) has also been performed. Finally, results are compared with previous ALICE measurements in p-Pb collisions at root s= 5.02 TeV and with theoretical calculations. (C) 2020 European Organization for Nuclear Research. Published by Elsevier B.V.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
