Identifying groomed jet splittings in heavy-ion collisions

Abstract

Measurements of jet substructure in heavy-ion collisions may provide key insight to the nature of jet quenching in the quark-gluon plasma. Jet grooming techniques from high-energy physics have been applied to heavy-ion collisions in order to isolate theoretically controlled jet observables and explore possible modification to the hard substructure of jets. However, the grooming algorithms used have not been tailored to the unique considerations of heavy-ion collisions, in particular to the experimental challenge of reconstructing jets in the presence of a large underlying event. We report a set of simple studies illustrating the impact of the underlying event on identifying groomed jet splittings in heavy-ion collisions, and on associated groomed jet observables. We illustrate the importance of the selection of grooming algorithm, as certain groomers are more robust to these effects, while others, including those commonly used in heavy-ion collisions, are susceptible to large background effects -- which, when uncontrolled, can mimic a jet quenching signal. These experimental considerations, along with appropriate theoretical motivation, provide input to the choice of grooming algorithms employed in heavy-ion collisions.

Final version after journal review

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Cited by in corpus (18)

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• Resolving the Scales of the Quark-Gluon Plasma with Energy Correlators
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• Measurement of substructure-dependent jet suppression in Pb+Pb collisions at 5.02 TeV with the ATLAS detector
• Measurements of the groomed and ungroomed jet angularities in pp collisions at $\sqrt{s}=5.02$ TeV
• Differential measurements of jet substructure and partonic energy loss in Au$+$Au collisions at $\sqrt{s_{\mathrm{NN}}}=200$ GeV
• Dead-cone searches in heavy-ion collisions using the jet tree
• Dynamical grooming meets LHC data
• Isolating perturbative QCD splittings in heavy-ion collisions
• Measurements of the groomed jet radius and momentum splitting fraction with the soft drop and dynamical grooming algorithms in pp collisions at $\sqrt{s}=5.02$ TeV
• Minijet quenching in non-equilibrium quark-gluon plasma
• Identifying quenched jets in heavy ion collisions with machine learning
• Measurement of inclusive and leading subjet fragmentation in pp and Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• Search for quasi-particle scattering in the quark-gluon plasma with jet splittings in pp and Pb$-$Pb collisions at $\sqrt{{\text{s}}_{\mathrm{NN}}}=5.02$ TeV
• Medium-induced modification of groomed and ungroomed jet mass and angularities in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV
• Measurement of the groomed jet radius and momentum splitting fraction in pp and Pb$-$Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV
• Studying the QGP with Jets at the LHC and RHIC