Generalized angularities measurements from STAR at √SNN = 200 GeV

Abstract

Jets are produced in early stages of heavy-ion collisions and undergo modified showering in the quark-gluon plasma (QGP) medium relative to a vacuum case. These modifications can be measured using observables like jet momentum profile and generalized angularities to study the details of jetmedium interactions. Jet momentum profile (ρ(r)) encodes radially differential information about jet broadening and has shown migration of charged energy towards the jet periphery in Pb+Pb collisions at the LHC. Measurements of generalized angularities (girth g and momentum dispersion pTD) and LeSub (difference between leading and subleading constituents) from Pb+Pb collisions at the LHC show harder, or more quark-like jet fragmentation, in the presence of the medium. Measuring these distributions in heavy-ion collisions at RHIC will help us further characterize the jet-medium interactions in a phase-space region complimentary to that of the LHC. In this contribution, we present the first measurements of fully corrected g, pTD and LeSub observables using hard-core jets in Au+Au collisions at √SNN = 200 GeV, collected by the STAR experiment at RHIC.