Abstract

Distributions sensitive to the underlying event are studied in events containing one or more charged particle jets produced in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector at the Large Hadron Collider (LHC). These measurements reflect 800 ub-1 of data taken during 2010. Jets are reconstructed using the anti-kt algorithm with radius parameter R varying between 0.2 and 1.0. Distributions of the charged-particle multiplicity, the scalar sum of the transverse momentum of charged particles, and the average charged-particle pT are measured as functions of pjetT in regions transverse to and opposite the leading jet for 4 GeV<pjetT < 100 GeV. In addition, the R dependence of the mean values of these observables is studied. In the transverse region, both the multiplicity and the scalar sum of the transverse momentum at fixed pjetT vary significantly with R, while the average charged-particle transverse momentum has a minimal dependence on R. Predictions from several Monte Carlo tunes have been compared to the data; the predictions from Pythia 6, based on tunes that have been determined using LHC data, show reasonable agreement with the data, including the dependence on R. Comparisons with other generators indicate that additional tuning of soft-QCD parameters is necessary for these generators. The measurements presented here provide a testing ground for further development of the Monte Carlo models.

Autore Pugliese

• Gorini Edoardo , Spagnolo Stefania Antonia , Ventura Andrea

Tutti gli autori

• G. AAD , M. BIANCO , G. CHIODINI , E. GORINI , M. PRIMAVERA , S. SPAGNOLO , A. VENTURA , ET AL.

Titolo volume/Rivista

PHYSICAL REVIEW D, PARTICLES, FIELDS, GRAVITATION, AND COSMOLOGY

Anno di pubblicazione

2012

ISSN

1550-7998

ISBN

Non Disponibile

Numero di citazioni Wos

36

Ultimo Aggiornamento Citazioni

28/04/2018

Numero di citazioni Scopus

16

Ultimo Aggiornamento Citazioni

28/04/2018

Settori ERC

Non Disponibile

Codici ASJC

Non Disponibile