Soft QCD at the LHC

par Dr Gerhard Brandt (DESY)

vendredi 28 janv. 2011, 14:00 → 15:00 Europe/Paris

Auditorium M. Vivargent (LAPP)

Soft QCD processes form an important background to high p_T physics in pp collisions at the LHC. It is therefore important to measure them precisely and improve their modelling via Monte Carlo generator tuning. We present measurements of charged particle distributions at centre-of-mass energies sqrt(s)=0.9 and 7 TeV. The distributions are also shown in diffraction suppressed and diffraction enhanced minimum bias event samples. Underlying event distributions, where the charged particle density in a region transverse to the hard interaction is plotted as a function of the transverse momentum of the leading charged particle, are also presented. A new ATLAS tune to the diffraction suppressed minimum bias and underlying event data is presented. Also applications to luminosity measurement and cross-experiment comparisons are demonstrated.

Slides softQCDatLHC.LAPP.pdf