Radial profile of bottom quarks in jets in high-energy nuclear collisions * *Supported by the Guangdong Major Project of Basic and Applied Basic Research (2020B0301030008), the Science and Technology Program of Guangzhou (2019050001) and the NSFC of China with Project (11935007, 11805167)

Abstract

Angular correlations between a heavy quark (HQ) and its tagged jet are potentially new tools to gain insight into the in-medium partonic interactions in relativistic heavy-ion collisions. In this work, we present the first theoretical study on the radial profiles of B mesons in jets in Pb+Pb collisions at the Large Hadron Collider (LHC). The initial production of a bottom quark tagged jet in p+p is computed by SHERPA, which matches the next-to-leading order matrix elements with contributions of parton showers, whereas the massive quark traversing the quark-gluon plasma is described by a Monte Carlo model, SHELL, which can simultaneously simulate light and heavy flavor in-medium energy loss within the framework of Langevin evolution. In p+p collisions, we find that at lower the radial profiles of heavy flavors in jets are sensitive to the heavy quark mass. In 0-10% Pb+Pb collisions at TeV, we observe an inverse modification pattern of the B meson radial profiles in jets at GeV compared to those of D mesons: the jet quenching effects narrow the jet radial profiles of B mesons in jets while broadening those of D mesons in jets. We find that in A+A collisions, the contribution dissipated from the higher GeV region naturally has a narrower initial distribution and consequently leads to a narrower modification pattern of the radial profile; however the diffusion nature of the heavy flavor in-medium interactions will give rise to a broader modification pattern of the radial profile. These two effects consequently compete and offset with each other, and the b quarks in jets benefit more from the former and suffer less diffusion effect compared to that of c quarks in jets. These findings can be tested in the future experimental measurements at the LHC to gain better understanding of the mass effect of jet quenching.