IFLP   13074
INSTITUTO DE FISICA LA PLATA
Unidad Ejecutora - UE
artículos
Título:
Charged-particle multiplicities in pp interactions measured with the ATLAS detector at the LHC.
Autor/es:
ANDUAGA, XABIER SEBASTIAN; THE ATLAS COLLABORATION
Revista:
NEW JOURNAL OF PHYSICS
Editorial:
IOP PUBLISHING LTD
Referencias:
Año: 2010 p. 53033 - 53103
ISSN:
1367-2630
Resumen:
Measurements are presented from proton-proton collisions at
centre-of-mass energies of sqrt(s) = 0.9, 2.36 and 7 TeV recorded with
the ATLAS detector at the LHC. Events were collected using a single-arm
minimum-bias trigger. The charged-particle multiplicity, its dependence
on transverse momentum and pseudorapidity and the relationship between
the mean transverse momentum and charged-particle multiplicity are
measured. Measurements in different regions of phase-space are shown,
providing diffraction-reduced measurements as well as more inclusive
ones. The observed distributions are corrected to well-defined
phase-space regions, using model-independent corrections. The results
are compared to each other and to various Monte Carlo models, including a
new AMBT1 PYTHIA 6 tune. In all the kinematic regions considered, the
particle multiplicities are higher than predicted by the Monte Carlo
models. The central charged-particle multiplicity per event and unit of
pseudorapidity, for tracks with pT >100 MeV, is measured to be 3.483
+- 0.009 (stat) +- 0.106 (syst) at sqrt(s) = 0.9 TeV and 5.630 +- 0.003
(stat) +- 0.169 (syst) at sqrt(s) = 7 TeV.