Showing 1–3 of 3 results for author: Altenburger, A

Pre-hydrodynamic jet momentum broadening beyond the jet quenching parameter

Authors: Alois Altenburger, Kirill Boguslavski, Florian Lindenbauer

Abstract: We obtain the collision kernel and related dipole cross section during the initial nonequilibrium stages in heavy-ion collisions. These quantities are a crucial input for jet quenching calculations. We further compute the gluon splitting rates in the AMY formalism resulting from this nonequilibrium kernel. Comparing with thermal and commonly used forms, we find that particularly the gluon splittin… ▽ More We obtain the collision kernel and related dipole cross section during the initial nonequilibrium stages in heavy-ion collisions. These quantities are a crucial input for jet quenching calculations. We further compute the gluon splitting rates in the AMY formalism resulting from this nonequilibrium kernel. Comparing with thermal and commonly used forms, we find that particularly the gluon splitting rate for parton energies of the order of the hard effective temperature significantly differs from these approximations. △ Less

Submitted 30 September, 2025; originally announced September 2025.

Comments: 4 pages, 2 figures; Quark Matter 2025 conference proceedings

Report number: MIT-CTP/5933

Jet momentum broadening beyond the jet quenching parameter from QCD kinetic theory

Authors: Alois Altenburger, Kirill Boguslavski, Florian Lindenbauer

Abstract: Using QCD kinetic theory, we study momentum broadening of jets using the full broadening probability (elastic collision kernel) $C(\mathbf{q_\perp})$ extracted during simulations of the nonequilibrium initial stages in heavy-ion collisions. We find that small momentum transfer is more likely than in thermal equilibrium, particularly along the beam axis. Our extraction represents a significant step… ▽ More Using QCD kinetic theory, we study momentum broadening of jets using the full broadening probability (elastic collision kernel) $C(\mathbf{q_\perp})$ extracted during simulations of the nonequilibrium initial stages in heavy-ion collisions. We find that small momentum transfer is more likely than in thermal equilibrium, particularly along the beam axis. Our extraction represents a significant step towards a more realistic modeling of jet quenching during the initial stages. △ Less

Submitted 6 September, 2025; originally announced September 2025.

Comments: 6 pages, 4 figures; Proceedings to Hard Probes 2024; accepted for publication in EPJ Web of Conferences

Jet broadening and radiation in the early anisotropic plasma in heavy-ion collisions

Authors: Alois Altenburger, Kirill Boguslavski, Florian Lindenbauer

Abstract: Measuring the energy loss of energetic jet partons may provide experimental opportunities to constrain the initial nonequilibrium stages in heavy-ion collisions, which requires theoretical predictions for the jet-medium potential. In this letter, we go beyond the usual harmonic approximation, extract this potential for the first time using QCD kinetic theory simulations, and provide a simple cutof… ▽ More Measuring the energy loss of energetic jet partons may provide experimental opportunities to constrain the initial nonequilibrium stages in heavy-ion collisions, which requires theoretical predictions for the jet-medium potential. In this letter, we go beyond the usual harmonic approximation, extract this potential for the first time using QCD kinetic theory simulations, and provide a simple cutoff-independent small-distance form. We find significant differences to thermal media at early times in momentum and position space, as well as substantial angular dependence. Applying our results to the gluon splitting rates using a novel computational method reveals tensions in the current kinetic theory implementations for early times. △ Less

Submitted 3 September, 2025; originally announced September 2025.

Comments: 5+7 pages, 3+3 figures

Report number: MIT-CTP/5917