Charged-particle multiplicity measurement in proton-proton collisions at root s=7 TeV with ALICE at LHC

0357527 - ÚJF 2011 RIV DE eng J - Journal Article
Aamodt, K. - Abel, N. - Abeysekara, U. - Abrahantes Quintana, A. - Abramyan, A. - Adamová, Dagmar - Bielčík, Jaroslav - Bielčíková, Jana - Kapitán, Jan - Kushpil, Svetlana - Kushpil, Vasilij - Pachr, M. - Petráček, Vojtěch - Rak, Jan - Šumbera, Michal - Tlustý, David - Wagner, Vladimír - Mareš, Jiří A. - Polák, Karel - Závada, Petr … Total 1062 authors
Charged-particle multiplicity measurement in proton-proton collisions at root s=7 TeV with ALICE at LHC.
European Physical Journal C. Roč. 68, 3-4 (2010), s. 345-354. ISSN 1434-6044. E-ISSN 1434-6052
R&D Projects: GA MŠMT LA08015
Institutional research plan: CEZ:AV0Z10480505; CEZ:AV0Z10100502
Keywords : PSEUDORAPIDITY DISTRIBUTIONS * PP INTERACTIONS * ENERGIES
Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders
Impact factor: 3.248, year: 2010

The pseudorapidity density and multiplicity distribution of charged particles produced in proton-proton collisions at the LHC, at a centre-of-mass energy root s = 7 TeV, were measured in the central pseudorapidity region vertical bar eta vertical bar < 1. Comparisons are made with previous measurements at root s = 0.9 TeV and 2.36 TeV. At root s = 7 TeV, for events with at least one charged particle in |eta vertical bar| < 1, we obtain dN(ch)/d eta = 6.01 +/- 0.01(stat.)(-0.12)(+0.20) (syst.). This corresponds to an increase of 57.6%+/-0.4%(stat.)(-1.8%)(+3.6) (syst.) relative to collisions at 0.9 TeV, significantly higher than calculations from commonly used models. The multiplicity distribution at 7 TeV is described fairly well by the negative binomial distribution.
Permanent Link: http://hdl.handle.net/11104/0195784