Holographic light quark jet quenching in flavor resolved QCD plasmas

Abstract

We investigate light quark energy loss in a quark-gluon plasma using the holographic falling string setup. Stopping distances are computed from null geodesics in an Einstein-Maxwell-dilaton (EMD) background whose thermodynamics are lattice calibrated for three compositions: pure glue, two flavor QCD, and full QCD with strangeness. This geometry mirrors that of recent shooting string simulations, enabling a direct comparison between integrated stopping lengths and differential energy loss. Systematic scans over temperature, baryon chemical potential, and path length reveal that near the QCD crossover, plasmas with more dynamical flavors exhibit stronger quenching, consistent with RHIC strange hadron suppression data. At higher temperatures, approaching the conformal regime, this flavor hierarchy reverses, a trend absent in flavorless models. Finite baryon chemical potential shortens stopping distances and enhances energy loss, with marked sensitivity near the QCD critical endpoint, mirroring anomalies observed in RHIC beam energy scans. Consistent trends from these two independent holographic observables rule out formalism specific artifacts and support the reliability of our lattice calibrated EMD framework. We further discuss the geometric origin of the high temperature flavor ordering, parameter sensitivities, and possible extensions to heavy ion transport simulations.