# Initial Stages 2021

Jan 10 – 15, 2021
Weizmann Institute of Science
Asia/Jerusalem timezone
See you at IS2023 in Copenhagen in June 2023

## Measurement of the jet-particle $v_{2}$ in p--Pb collisions at $\sqrt{s_{\rm NN}}=5.02$~TeV with ALICE at the LHC

Jan 10, 2021, 7:45 PM
1h 30m
Patio (vDLCC)

### Patio

#### vDLCC

bullet talk (poster) The initial stages of heavy-ion collisions

### Speaker

Siyu Tang (Central China Normal University CCNU (CN))

### Description

In heavy-ion collisions, the observed non-zero second-order azimuthal anisotropy coefficient, $v_{2}$, for particles with high transverse momenta $\it{p}_{\rm T}$ is driven by the path-length dependent energy loss of hard partons travelling in the QGP, known as the jet quenching effect. Recent measurements show also a non-zero $v_{2}$ values for high $\it{p}_{\rm T}$ charged particles at high multiplicities in small collision systems (pp and p--Pb). Various mechanisms, such as parton energy loss in the cold nuclear matter, hydrodynamic evolution in the final state and initial state gluon correlations, are proposed to describe the observations whose origin is still debated.

In this contribution, the $v_{2}$ of particles within jets at mid-rapidity ($-0.8 < \eta < 0.8$) in the $10\%$ most central p--Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$~TeV, measured with the ALICE detector, is presented. The $v_{2}$ signal of jet particles is extracted with 2-particle correlation method using a template fit and subsequently long-range correlations with particles at forward rapidities. The non-flow contribution is suppressed by subtracting the low-multiplicity from high-multiplicity collisions. The measurements will provide new insight into the understanding of the origin of long-range correlations observed in small systems.

### Primary author

Siyu Tang (Central China Normal University CCNU (CN))

### Presentation materials

 ST_IS2021.m4v ST_IS2021.pdf