# EPS-HEP2021 conference

26-30 July 2021
Zoom
Europe/Berlin timezone

## Measurements of jet quenching via hadron+jet correlations in Pb-Pb and high-particle multiplicity pp collisions with ALICE

26 Jul 2021, 11:30
15m
Zoom

#### Zoom

Parallel session talk Heavy Ion Physics

Artem Kotliarov

### Description

Interactions of high-$p_{T}$ partons with quark-gluon plasma (QGP) result in jet quenching, which is manifest by the suppression of high-$p_{T}$ jet yields and the modification of jet substructure and di-jet acoplanarity distributions.
Several jet quenching phenomena can be measured precisely over a wide range of jet $p_{T}$ using semi-inclusive distributions of charged-particle jets recoiling from a high-$p_{T}$ trigger hadron, which incorporate data-driven suppression of the large uncorrelated background produced in heavy-ion collisions.

In this talk we report semi-inclusive measurements of hadron-jet acoplanarity in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}} = 5.02$ TeV and high-particle multiplicity pp collisions at $\sqrt{s} = 13$ TeV. In the Pb-Pb system, where QGP formation is established, narrowing of the acoplanarity is observed relative to a reference distribution from pp collisions. In contrast, pp events with high-particle multiplicity exhibit a broadening of the acoplanarity relative to minimum bias events. In this case, however, qualitatively similar features are also seen in pp collisions generated by PYTHIA, which does not include jet quenching or other QGP effects. We will discuss the current status of these analyses, and prospects to understand the origin of these striking phenomena.

Collaboration / Activity ALICE alice-cc-chairs@cern.ch ALICE CC Chairs