# 2nd International Workshop on QCD Challenges from pp to AA

October 31, 2017 to November 3, 2017
Other Institutes
America/Mexico_City timezone
Call for abstracts

## Energy density and path-length dependence of the fractional momentum loss in heavy-ion collisions at $\sqrt{s_{\rm NN}}$ from 62.4 to 5020 GeV

Nov 2, 2017, 5:45 PM
25m
Other Institutes

#### Other Institutes

Edificio Carolino, Benemerita Universidad Autonoma de Puebla, 4 Sur 104 Col Centro. Puebla City, Mexico

### Speaker

Omar Vázquez Rueda (Universidad Nacional Autonoma (MX))

### Description

In this work a study of the fractional momentum loss ($S_{\rm loss}$) as a function of the characteristic path-length ($L$) and the Bjorken energy density times the equilibration time ($\epsilon_{\rm Bj}\tau_{0}$) for heavy-ion collisions at different $\sqrt{s_{\rm NN}}$ is presented. The study has been conducted using inclusive charged particles from intermediate to large transverse momentum ($5 < p_{\rm T} < 20$\,GeV/$c$). Within uncertainties and for all the transverse momentum values which were explored, the fractional momentum loss linearly increases with $({\epsilon_{\rm Bj}\tau_{0}})^{3/8}$$L. The functional form of S_{\rm loss} vs. ({\epsilon_{\rm Bj}\tau_{0}})^{3/8}$$L$ seems to be universal. Moreover, for identified charged hadrons a linear relationship between $S_{\rm loss}$ and $L$ is also observed. The behaviour of data could provide important information aimed to understand the parton energy loss mechanism in heavy-ion collisions and some insight into the expected effect for small systems.

### Primary author

Omar Vázquez Rueda (Universidad Nacional Autonoma (MX))