Abstract

The high energy densities deposited in the aftermath of heavy-ion collisions, promote a phase transition in QCD to a novel state of deconfined quarks and gluons, known as the quark-gluon plasma. Due to the running of the strong coupling, the emergent properties of this medium are strongly scale dependent, with soft interactions revealing a strongly bound state of quasi-particles. A long sought after signature of deconfinement is high-momentum transfer scatterings of a probe off of weakly bound quarks and gluons in the medium. This phenomenon is known as Molière scatterings and can be accessed through measurements of jets which traverse and interact with the medium. In this talk a theoretical overview of Molière scattering and its implications for the properties of the quark-gluon plasma will be presented, followed by the presentation of an experimental measurement using the substructure of jets to probe these high-momentum scatterings of partons in the shower.

Speakers

Adam Takacs

is a postdoctoral researcher at Heidelberg University and obtained his PhD from the University of Bergen in 2023. He is joining the CERN Theory Department through a recent Norwegian research grant to work on the theoretical and phenomenological description of jets in heavy-ion collisions.

Raymond Ehlers
is an experimental physicist at UC Berkeley and Lawrence Berkeley National Laboratory. He is a member of the ALICE collaboration, where he co-leads the Jet and Hard Photon working group, and the theory-experiment JETSCAPE collaboration. He received his PhD from Yale University in 2020, has held postdoctoral positions at Oak Ridge National Lab and Lawrence Berkeley National Labs, and is currently an Assistant Project Scientist at UC Berkeley. His research focuses on investigations of QCD matter under extreme conditions, characterizing the properties of the quark-gluon plasma through measurements of jets and their substructure, as well as through their rigorous comparison to theoretical calculations.