Particle Production as a Function of Underlying-event Activity and Search for Jet-like Modifications in \(pp\), \(p\)–Pb, and Pb–Pb Collisions at \(\sqrt {s_{NN}}=5.02\)\thinspace TeV with ALICE

The similarity between small- and large-collision systems is explored using the charged-particle multiplicity in the transverse region, N Tch , which is sensitive to the underlying event. Measurements of charged-particle production as a function of N Tch in pp, p–Pb and Pb–Pb collisions at √ s NN = 5 . 02 TeV in the toward, away and transverse regions are discussed. These three regions are deﬁned relative to the track with the largest transverse momentum in the event ( p trigT ). The activity in the transverse region is subtracted from the activity in the toward and the away regions to search for jet-like modiﬁcations in small-collision systems. The jet-like signals are studied both as a function of N T ch and p trigT . Results are compared with two general purpose Monte Carlo event generators: PYTHIA 8 and EPOS LHC.