Constraint fitting of experimental data with a jet quenching model embedded in a hydrodynamical bulk medium

TL;DR

This paper performs a comprehensive fit of high-$p_T$ particle suppression data in heavy-ion collisions using a hydrodynamical medium and finds that the transport coefficient $$ is significantly larger than perturbative estimates, indicating strong medium effects.

Contribution

It introduces a global fitting approach combining jet quenching weights with hydrodynamical models, providing new constraints on the medium's transport properties in heavy-ion collisions.

Findings

Preferred $$ values are over four times larger than perturbative estimates.

Heavy quark data are statistically compatible with a radiative energy loss scenario.

Results are sensitive to nuclear PDFs and pre-hydrodynamical energy loss assumptions.

Abstract

We present a global fit to single- and double-inclusive suppression data of high-$p_T$ particles in central Au+Au collisions at top RHIC energy. We also include in this analysis data on heavy quarks via their D and B meson semi-leptonic decays (i.e. non-photonic electrons). The analysis is based on the parton quenching weights for medium-induced gluon radiation computed in the BDMPS approximation then embedded in a hydrodynamical description of the bulk medium. Our results indicate that values of the transport coefficient $\hat q$ more than four times larger than perturbative estimates are preferred by experimental data. This confirms previous calculations based on simpler implementations of the medium geometry or only the single-inclusive suppression. We also comment on the statistical compatibility of the heavy quark data within a radiative only energy loss scenario, and on the sensitivity of the results to nuclear modification of the parton distribution functions (PDFs) and to assumptions on the energy loss during times in the collision prior to the hydrodynamical behavior.}