Measurement of the underlying event activity at the LHC with root s=7 TeV and comparison with root s=0.9 TeV

Abstract

A measurement of the underlying activity in events with a jet of transverse momentum in the several GeV region is performed in proton-proton collisions at root s = 0.9 and 7 TeV, using data collected by the CMS experiment at the LHC. The production of charged particles with pseudorapidity vertical bar eta vertical bar < 2 and transverse momentum p(T) > 0.5 GeV = c is studied in the azimuthal region transverse to that of the leading set of charged particles forming a track-jet. A significant growth of the average multiplicity and scalar-p(T) sum of the particles in the transverse region is observed with increasing p(T) of the leading track-jet, followed by a much slower rise above a few GeV/c. For track-jet p(T) larger than a few GeV/c, the activity in the transverse region is approximately doubled with a centre-of-mass energy increase from 0.9 to 7 TeV. Predictions of several QCD-inspired models as implemented in PYTHIA are compared to the data.


Tutti gli autori

  • POMPILI A.;MARANGELLI B.;CALABRIA C.;SELVAGGI G.;LUSITO L.;BARBONE L.;ABBRESCIA M.;DE PALMA M.;PACIFICO N.;MY S.;NUZZO S.V.

Titolo volume/Rivista

Non Disponibile


Anno di pubblicazione

2011

ISSN

1029-8479

ISBN

Non Disponibile


Numero di citazioni Wos

Nessuna citazione

Ultimo Aggiornamento Citazioni

Non Disponibile


Numero di citazioni Scopus

90

Ultimo Aggiornamento Citazioni

Non Disponibile


Settori ERC

Non Disponibile

Codici ASJC

Non Disponibile