Precision measurements of jet substructure are used as a probe of fundamental QCD processes. The primary Lund jet plane density is a two-dimensional visual representation of the radiation off the primary emitter within the jet that can be used to isolate different regions of the QCD phase space. We present a new measurement with the ALICE detector of the primary Lund plane density for...
Jets are algorithmic proxies of hard scattered quarks/gluons created in collisions of high energy particles. In the last few years, there has seen an explosion of jet substructure results from all experiments derived from exploiting clustering algorithms. Jet quenching via parton energy loss in heavy ion collisions is an established probe for exploring the properties of the quark-gluon plasma....
We tried to locate the initial jet production positions in QGP, using the jet energy loss along the path length direction, the asymmetry perpendicular to the path length from gradient-tomography and the energy momentum distribution inside the jet with deep learning. These machine learning assisted Jet tomography help to locate the jet production positions with reasonable precision that helps...
We present the scale dependence of the jet-medium interactions seen in the modification of jet substructure observables in high-energy heavy-ion collisions by systematic studies with JETSCAPE 3, a publicly available software package of a framework for Monte Carlo event generators [1]. In high-energy heavy-ion collisions, jet partons interact with the quark-gluon plasma medium while changing...
The evolution of leading partons and jets through deconfined QCD matter is a multi-scale phenomenon and remains as one of the challenging problems in heavy-ion physics. To address this, we use the JETSCAPE framework [1] in which the production of the hard parton is factorized from the evolution of the produced QGP. To incorporate various scales involved in the jet-medium interaction during the...
Jets are collimated sprays of hadrons and serve as an experimental tool for studying the dynamics of quarks and gluons. In particular, differential measurements of jet substructure enable a systematic exploration of the parton shower evolution. The SoftDrop grooming technique utilizes the angular ordered Cambridge/Aachen reclustering tree and provides a correspondence between the experimental...
So far, analytical jet quenching formalisms have either assumed that modifications to the jets’ structure are dominated by a few hard in-medium scatterings or by multiple soft interactions. However, it is known that neither of these regimes corresponds to any currently available experimental set-up, and thus bridging the gap between these limits under a single framework is a crucial step...
Properties of dijets may provide sensitive probes of jet quenching in Quark-Gluon Plasma. Dijet invariant mass measurements in small systems provide an essential baseline for such studies in Pb-Pb collisions. In this poster, we present the first measurements of dijet invariant mass in minimum bias pp and p-Pb collisions at $\sqrt{s_\mathrm{NN}}=5.02$ TeV by ALICE. Jets are clustered using the...
The different modification of quark- and gluon-initiated jets in the quark-gluon plasma produced in heavy-ion collisions is a long-standing question that has not yet received a definitive answer from experiments. In particular, the relative sizes of the modification of quark and gluon jets differ between theoretical models. Therefore a fully data-driven technique is crucial for an unbiased...
Different than for inclusive jets, leading jet cross sections constitute normalized probability distributions for the leading jet to carry a longitudinal momentum fraction relative to the initial fragmenting parton. The formation and evolution of leading jets can be described by jet functions that satisfy non-linear DGLAP-type evolution equations. We present a parton shower algorithm that...
Heavy-flavour (charm and beauty) jets are excellent probes to study Quantum Chromodynamics (QCD). Their precise measurements in proton-proton collisions are used to verify perturbative QCD calculations and improve our modelling capabilities by constraining Monte Carlo generators. They also serve as the reference measurements for more complex systems such as Pb–Pb collisions, helping to...
The phase transition from hadronic matter to quark-gluon plasma (QGP) is a phenomenon that occurs under extreme conditions of high temperature and high density, as achieved at the relativistic heavy ion collider (RHIC). The QGP causes energy loss of high momentum particles which is observed as suppression of high momentum hadron production in A+A collisions relative to p+p collisions. The...
The jet transverse momentum diffusion coefficient $\hat{q}$ is an important transport coefficient governing the radiative energy loss of a parton propagating the Quark-Gluon Plasma (QGP) created in Heavy-Ion Collisions. Based on perturbative arguments [1], which were recently extended to next-to-leading order [2], the dimensionless ratio $\hat{q}/T^3$ was shown to be connected with the...