Naslov
Charged-particle multiplicity measurement in proton–proton collisions at sqrt(s)=0.9 and 2.36 TeV with ALICE at LHC

Autori
Aamodt, K. ; ... ; Antičić, Tome ; ... ; Gotovac, Sven ; ... ; Mudnić, Eugen ; ... ; Šuša, Tatjana ; ... ; Vicković, Linda ; ... ; Zynovyev, M. (The ALICE Collaboration)

Izvornik
European physical journal C : particles and fields (1434-6044) 68 (2010), 1/2; 89-108

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
LHC; ALICE; p+p; charged-particle; multiplicity

Sažetak
Charged-particle production was studied in proton–proton collisions collected at the LHC with the ALICE detector at centre-of-mass energies 0.9 TeV and 2.36 TeV in the pseudorapidity range |η| < 1.4. In the central region (|η| < 0.5), at 0.9 TeV, we measure charged-particle pseudorapidity density dNch/dη = 3.02 ± 0.01(stat.) +0.08 −0.05(syst.) for inelastic interactions, and dNch/dη = 3.58 ± 0.01 (stat.) +0.12 −0.12(syst.) for non-single-diffractive interactions. At 2.36 TeV, we find dNch/dη = 3.77 ± 0.01(stat.) +0.25 −0.12(syst.) for inelastic, and dNch/dη = 4.43 ± 0.01(stat.) +0.17 −0.12(syst.) for non-single-diffractive collisions. The relative increase in charged-particle multiplicity from the lower to higher energy is 24.7% ± 0.5%(stat.) +5.7 −2.8%(syst.) for inelastic and 23.7% ± 0.5%(stat.) +4.6 −1.1%(syst.) for non-single-diffractive interactions. This increase is consistent with that reported by the CMS collaboration for non-single-diffractive events and larger than that found by a number of commonly used models. The multiplicity distribution was measured in different pseudorapidity intervals and studied in terms of KNO variables at both energies. The results are compared to proton– antiproton data and to model predictions.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA