Through analytical arguments, numerical calculations and comparison with experimental data, we show that the ratio of high-$p_{\perp}$ observables $v_2/(1-R_{AA})$ reaches a well-defined saturation value at high $p_{\perp}$, which depends on the spatial anisotropy of quark-gluon plasma formed in ultrarelativistic heavy ion collisions. By using our recently developed DREENA framework, which can...
The theory of jet quenching has been steadily evolving in order to incorporate the effects of having a longitudinally evolving plasma. On the other hand, the transverse dynamics of the medium evolution has been largely ignored due to the fact that its effects are suppressed by powers of the energy of the probe. Recently, a calculation of the effects of medium motion on transverse momentum...
The quark-gluon plasma formed in heavy-ion collisions has a large momentum anisotropy, especially during early stages of collisions. For jet partons this leads to momentum broadening which is not isotropic in the parton's transverse plane. In this talk we discuss such anisotropic momentum broadening of jets in detail and evaluate how it changes the radiation of hard gluons, and gives rise to a...
Hard probes, due to their large momenta (or masses), are produced only through hard interactions with large momentum transfer at the earliest phase of a heavy-ion collision. They then propagate through the evolving medium probing QCD matter at different energy scales and different phases of the fireball evolution. During this propagation heavy quarks and high-$p_T$ partons lose a substantial...
Jet substructure applied to a heavy-ion environment can provide valuable information about jet-medium interaction. This class of observables, mostly inherited from proton-proton collisions, is still far from being fully exploited as a tool for QGP tomography. So far, measurements are restricted to quantities that provide an average quantification of the medium parameters, missing the critical...
Recently, we developed a framework to evaluate the single-inclusive gluon emission spectrum without further assumptions, including full resummation of multiple scatterings. In this talk, we compare this formalism with well-known analytical approximations, determining in that way their validity in all kinematical regions and showing to what extent accounting for multiple scatterings is crucial...
The injection of energy and momentum from a jet into the QGP generates a wake, which leads to soft and semi-hard particle creation correlated with the jet direction after the QGP hadronizes. As several jet quenching studies have shown, this medium response phenomenon plays a crucial role in our understanding of many jet structure and substructure observables. Nevertheless, a detailed account...
Partonic jets, i.e. highly energetic collimated sprays of strongly interacting particles, provide an excellent means to study the hot and dense medium
of a quark gluon plasma (QGP), since the highly energetic jet particles interact with the medium particles, however do not thermalize.
Jet particles in the medium undergo both processes of scatterings off medium particles as well as emission...
Measurements of jet profiles in high-energy collisions are sensitive probes of QCD parton splitting and showering. Precise understanding of the jet structures are essential for setting the baseline not only for nuclear modification of jets in heavy-ion collisions, but also for possible semi-soft cold QCD effects such as multi-parton interactions (MPI) that may modify jets in high-multiplicity...
The interaction between the jet and QGP fluid will deflect particles associated with the jet from their initial orientation. Such deflection will depend on the energy of the jet constitutes and the velocity of the flow. The soft particles suffering stronger deflection will drift towards the direction of the flowing medium, away from the center of the jet cone where the hard particles are...
We employ machine learning techniques to identify important features that distinguish jets produced in heavy-ion collisions from jets produced in proton-proton collisions [1]. We formulate the problem using binary classification and focus on leveraging machine learning in ways that inform theoretical calculations of jet modification: (i) we quantify the information content in terms of Infrared...
Study of modification of the substructure of charged jets due to the presence of medium provides insight into the energy loss mechanisms of jets in the medium. We have studied the in-medium modification of two jet-shape observables, differential jet-shape ($\rho(r)$) and angularity ($g$) in PbPb collisions at $\sqrt{s_{NN}}$=2.76 TeV using JEWEL and EPOS event generators. While JEWEL (recoil...
Measurements of reconstructed jets and jet substructure offer opportunities to study fragmentation in a nuclear environment. Jet measurements in $p$+A collisions can provide crucial information for understanding the relationship between hard and soft processes in small collision systems. However, at RHIC this promise is complicated by the low jet energies and lack of hadronic calorimetry in...
Jet substructure is a powerful tool to probe the perturbative regime of jet evolution in proton-proton and heavy-ion collisions. Over the past few years, a wide variety of substructure observables have been proposed in order to understand specific aspects of jet dynamics in a quark-gluon plasma (QGP).
In this talk, based on [1], we will explore the ability of such an observable, called...
