Particle production as a function of underlying-event activity and very forward energy with ALICE

Abstract

Measurements of charged-particle production in pp and p-Pb collisions at √SNN=5.02 TeV in the toward, away and transverse regions are discussed. These three regions are defined event by event relative to the track with the largest transverse momentum (pTtrig). The transverse region is sensitive to the underlying event (UE), but it also includes contributions from initial-and final-state radiation (1SR-FSR). Therefore, it is further subdivided in two regions, defined according to their relative multiplicities: trans-max (the sub-transverse region with the larger multiplicity) and trans-min (the sub-transverse region with the smaller multiplicity) regions which have an enhanced sensitivity to ISR-FSR and UE, respectively. KNO-like scaling properties are explored in the three defined regions. Finally, the relationship between pTtrig and the energy detected in a region close to beam rapidity (very forward energy) is reported.