Jet and underlying event properties as a function of particle multiplicity in proton-proton collisions at 7 TeV

2 Dec 2013, 12:10
Talk MPI & Monte Carlo MPI & Monte Carlo


Maxim Azarkin (Russian Academy of Sciences (RU))


Characteristics of multiparticle production in proton-proton collisions at a centre-of-mass energy of 7 TeV are presented as a function of the charged-particle multiplicity. The produced particles are separated into those belonging to jets and those belonging to the underlying event (UE). Results are compared to the predictions of the PYTHIA and HERWIG Monte Carlo event generators. For increasing charge particle multiplicities, PYTHIA systematically predicts higher jet rates and harder transverse momenta spectra than seen in the data, whereas HERWIG shows the opposite trends. Predictions without multiparton interactions fail completely to describe the dependence observed in the data. In the lowest-multiplicity events, the data show narrower jets than predicted by both Monte Carlo event generators.

Primary author

Maxim Azarkin (Russian Academy of Sciences (RU))

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