Bonn 2010 – wissenschaftliches Programm
HK 62.5: Vortrag
Freitag, 19. März 2010, 15:00–15:15, HG I
Study of the Underlying Event in pp collisions with the ALICE experiment at LHC — •Sara Vallero — Universitaet Heidelberg, Phys. Institut, Deutschland
Though the ALICE detector represents the dedicated heavy-ions experiment within the LHC project, its capabilities extend to the domain of pp interactions to provide an insight into unprecedented collisional energies as well as a reference for heavy-nuclei collisions. In the LHC energy regime QCD production of jets is expected to dominate over all other categories of elementary interactions. In a hadronic machine, though, a clear jet signature has to be decoupled from the Underlying Event. The latter is defined in this context as the sum of processes that build up the final state in a collision that has lead to a QCD 2 to 2 scattering. In our definition this includes: beam remnants, multi-partonic interactions and initial/final state radiation. We have implemented into the ALICE simulation and analysis framework the strategy applied by the CDF and STAR collaborations, where the properties of the Underlying Event are investigated in the so-called Transverse Regions on an event-by-event basis. With the aim of applying the same procedure within the ALICE experiment, we illustrate the feasibility of an early study relying only on charged particle tracks. The main results are based on Monte Carlo simulations. Our considerations are supported by 2009 data from pp collisions at √s = 900 GeV at LHC.