Investigating Hard Splittings via Jet Substructure in pp and Pb-Pb Collisions at $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV with ALICE

TL;DR

This study investigates jet substructure modifications in proton-proton and lead-lead collisions at 5.02 TeV using grooming techniques, aiming to understand medium-induced effects on jet splittings and potential scattering signatures within the Quark-Gluon Plasma.

Contribution

It applies grooming and Lund Plane techniques to analyze the hardest jet splittings in pp and Pb-Pb collisions, providing new insights into jet-medium interactions at high energies.

Findings

Identification of modifications in jet substructure in Pb-Pb collisions

Evidence of potential large transverse momentum kicks within the medium

Enhanced sensitivity to hard splittings using grooming methods

Abstract

Jets lose energy as they propagate through the Quark-Gluon Plasma, modifying their parton shower. Jet substructure, which provides access to the evolution of jet splittings, is expected to be sensitive to interactions between the medium and the jet, providing the opportunity to further constrain both jet and medium properties. By utilizing grooming techniques, we can focus on the most pertinent hard splittings. Of particular interest is the search for large transverse momentum kicks which may indicate the presence of point-like scatters within the Quark-Gluon Plasma. We explore the jet substructure of inclusive jets in pp and Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV, utilizing Soft Drop and other grooming methods, as well as the Lund Plane, in order to access the hardest jet splitting, with a particular focus on the hardest $k_{\mathrm{T}}$ splitting.