A measurement of the underlying event (UE) activity in proton-proton collisions is performed using events with charged-particle jets produced in the central pseudorapidity region (|η<sup>jet</sup>| < 2) and with transverse momentum 1 ≤ p<inf>T</inf> <sup>jet</sup> < 100 GeV. The analysis uses a data sample collected at a centre-of-mass energy of 2.76 TeV with the CMS experiment at the LHC. The UE activity is measured as a function of p<inf>T</inf> <sup>jet</sup> in terms of the average multiplicity and scalar sum of transverse momenta (p<inf>T</inf>) of charged particles, with |η| < 2 and p<inf>T</inf> > 0.5 GeV, in the azimuthal region transverse to the highest p<inf>T</inf> jet direction. By further dividing the transverse region into two regions of smaller and larger activity, various components of the UE activity are separated. The measurements are compared to previous results at 0.9 and 7 TeV, and to predictions of several Monte Carlo event generators, providing constraints on the modelling of the UE dynamics.[Figure not available: see fulltext.]

Measurement of the underlying event activity using charged-particle jets in proton-proton collisions at √s=2.76 TeV

CALVELLI, VALERIO;LO VETERE, MAURIZIO;TOSI, SILVANO;
2015-01-01

Abstract

A measurement of the underlying event (UE) activity in proton-proton collisions is performed using events with charged-particle jets produced in the central pseudorapidity region (|ηjet| < 2) and with transverse momentum 1 ≤ pT jet < 100 GeV. The analysis uses a data sample collected at a centre-of-mass energy of 2.76 TeV with the CMS experiment at the LHC. The UE activity is measured as a function of pT jet in terms of the average multiplicity and scalar sum of transverse momenta (pT) of charged particles, with |η| < 2 and pT > 0.5 GeV, in the azimuthal region transverse to the highest pT jet direction. By further dividing the transverse region into two regions of smaller and larger activity, various components of the UE activity are separated. The measurements are compared to previous results at 0.9 and 7 TeV, and to predictions of several Monte Carlo event generators, providing constraints on the modelling of the UE dynamics.[Figure not available: see fulltext.]
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11567/851005
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 14
  • ???jsp.display-item.citation.isi??? 11
social impact