26-30 July 2021
Europe/Berlin timezone

Underlying Event studies and search for jet modifications in pp and p-Pb collisions with ALICE at the LHC

Not scheduled


Poster QCD and Hadronic Physics T06: QCD and Hadronic Physics


Ahsan Mehmood Khan


It is well-established that high-multiplicity pp and p–Pb collisions exhibit various signatures associated with the formation of QGP in heavy-ion collisions. In this contribution, we present results obtained using Underlying Event (UE) techniques, used to measure the average number density and the average total transverse momentum ($p_{\rm T}$) in the Toward, Transverse, and Away regions with respect to the leading trigger particle, but employed in novel ways. A conventional UE analysis is applied in p-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV to test the similarities between pp and p-Pb collisions. The charged particle multiplicity in the Transverse UE-dominated region, $N_{\rm T}$, is used as a multiplicity estimator to establish relations between particle production in pp, p-Pb and Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV. The results are compared with predictions from QCD-inspired Monte Carlo event generators. Finally, the UE studies are used to search for jet modification by subtracting the UE contributions measured in the Transverse region from the Toward and the Away regions. These studies in terms of $N_{\rm T}$ are powerful tools to search for jet modification patterns from the smallest systems, events with multiplicities lower than the mean for minimum-bias pp collisions, to the largest systems, central heavy-ion collisions, in a coherent way.

Collaboration / Activity ALICE

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