عنوان

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

LA7230k8x2

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

[Article]

Aamodt, K; Abel, N; Abeysekara, U; Abrahantes Quintana, A; Abramyan, A; Adamová, D; Aggarwal, MM; Aglieri Rinella, G; Agocs, AG; Aguilar Salazar, S; Ahammed, Z; Ahmad, A; Ahmad, N; Ahn, SU; Akimoto, R; Akindinov, A; Aleksandrov, D; Alessandro, B; Alfaro Molina, R; Alici, A; Almaráz Aviña, E; Alme, J; Alt, T; et al.

The pseudorapidity density and multiplicity distribution of charged particles produced in proton-proton collisions at the LHC, at a centre-of-mass energy √s= 7 TeV, were measured in the central pseudorapidity region {pipe}η{pipe} < 1. Comparisons are made with previous measurements at √s = 0.9 TeV and 2.36 TeV. At √s = 7 TeV, for events with at least one charged particle in {pipe}η{pipe} < 1, we obtain dNch/dη = 6.01 ± 0.01(stat.)+0.20-0.12(syst.). This corresponds to an increase of 57.6% ± 0.4%(stat.)+3.6-1.8%(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. © 2010 CERN for the benefit of the ALICE collaboration.

2010

Lawrence Berkeley National Laboratory

[Article]

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