Speaker
Description
The underlying event (UE) has been studied in ALICE for pp collisions at $\sqrt{s}$ =5.02 TeV. The average number density and the average total transverse momentum ($p_{\rm T}$) are studied in the near, away and transverse regions as a function of the leading particle $p_{\rm T}$. Results at 5.02 TeV show qualitatively the same behavior as observed at different energies.
For the first time the UE studies were performed also in p--Pb collisions, available at LHC at the same center-of-mass energy as for pp collisions. The transverse region is the most sensitive to the underlying event, while the toward and away regions include both the UE and jet fragments from the hard partonic scattering. To isolate the jet-like signal, the event activity in the transverse region is subtracted from the toward and away regions. Results for the two colliding systems will be compared with predictions from event generators like PYTHIA 8 and EPOS-LHC.
