Speaker
Mr
andrea lucaroni
(Universita' degli Studi di Perugia & INFN)
Description
First measurement of the underlying activity in proton-proton collisions at √s =7TeV compared with 900 GeV is presented, using data collected by the CMS experiment at the LHC in 2009/2010. The Multiple Parton Interaction rate, the main component of the Underlying Event activity, and its energy dependence is studied measuring the charged multiplicity and the charged energy density in a region perpendicular to the plane of the hard 2-to-2 scattering. The direction of the hard scattering and the energy scale of the event is found using of the leading track-jet. Corrected results are presented, unfolding the detector effects to directly compare with Monte Carlo models predictions.
