Underlying Event Studies for LHC Energies
  Underlying event was originally defined by the CDF collaboration decades ago. Here we improve the original definition to extend our analysis for events with multiple-jets. We introduce a definition for surrounding rings/belts and based on this definition the jet- and surrounding-belt-excluded areas will provide a good underlying event definition. We inverstigate our definition via the multiplicity in the defined geometry. In parallel, mean transverse momenta of these areas also studied in proton-proton collisions at $\sqrt{s}=7$ TeV LHC energy. 
Gergely G\'abor Barnaf\"oldi, Andr\'as G. Ag\'ocs, P\'eter L\'evai
hep-ph