Living on the edge: radius effects in the angular substructure of heavy-ion jets

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Andres, Carlota, Holguin, Jack, Kimelman, Benjamin, Elayavalli, Raghav Kunnawalkam, Viinikainen, Jussi, Yang, Zhong
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912757275688960
author Andres, Carlota
Holguin, Jack
Kimelman, Benjamin
Elayavalli, Raghav Kunnawalkam
Viinikainen, Jussi
Yang, Zhong
author_facet Andres, Carlota
Holguin, Jack
Kimelman, Benjamin
Elayavalli, Raghav Kunnawalkam
Viinikainen, Jussi
Yang, Zhong
contents Jet substructure observables serve as essential tools for probing the quark-gluon plasma produced in relativistic heavy-ion collisions. Their interpretation, however, is often complicated by edge effects, which arise when correlated particles fall outside the reconstructed jet radius, introducing distortions that obscure the underlying QCD dynamics. In this work, we present a comprehensive phenomenological study of edge effects in soft-insensitive angular observables, taking the two-point energy correlator (EEC) as a representative example. We argue that these distortions scale linearly with the average angular separation between the winner-take-all and $E$-scheme axes $\langle ϕ\rangle$, and validate this behavior across proton-proton (p-p) simulations with Pythia8 and Herwig7, as well as lead-lead (Pb-Pb) simulations using JEWEL and CoLBT. In p-p collisions, edge effects are strongly suppressed, scaling as $(R_L/R)^4$, whereas medium-modified jets can exhibit larger distortions, with contributions scaling as $(R_L/R)^2$ and $(R_L/R)^4$. Taking Pb-Pb/p-p ratios of the EEC substantially reduces, but does not completely eliminate, these distortions, highlighting the need of accounting for edge effects in the interpretation of heavy-ion jet substructure measurements. Since edge effects are largely governed by the $\langle ϕ\rangle$ distribution, studying this distribution provides a new handle for benchmarking and constraining the modeling of edge effects in heavy-ion event generators.
format Preprint
id arxiv_https___arxiv_org_abs_2512_10026
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Living on the edge: radius effects in the angular substructure of heavy-ion jets
Andres, Carlota
Holguin, Jack
Kimelman, Benjamin
Elayavalli, Raghav Kunnawalkam
Viinikainen, Jussi
Yang, Zhong
High Energy Physics - Phenomenology
High Energy Physics - Experiment
Nuclear Experiment
Nuclear Theory
Jet substructure observables serve as essential tools for probing the quark-gluon plasma produced in relativistic heavy-ion collisions. Their interpretation, however, is often complicated by edge effects, which arise when correlated particles fall outside the reconstructed jet radius, introducing distortions that obscure the underlying QCD dynamics. In this work, we present a comprehensive phenomenological study of edge effects in soft-insensitive angular observables, taking the two-point energy correlator (EEC) as a representative example. We argue that these distortions scale linearly with the average angular separation between the winner-take-all and $E$-scheme axes $\langle ϕ\rangle$, and validate this behavior across proton-proton (p-p) simulations with Pythia8 and Herwig7, as well as lead-lead (Pb-Pb) simulations using JEWEL and CoLBT. In p-p collisions, edge effects are strongly suppressed, scaling as $(R_L/R)^4$, whereas medium-modified jets can exhibit larger distortions, with contributions scaling as $(R_L/R)^2$ and $(R_L/R)^4$. Taking Pb-Pb/p-p ratios of the EEC substantially reduces, but does not completely eliminate, these distortions, highlighting the need of accounting for edge effects in the interpretation of heavy-ion jet substructure measurements. Since edge effects are largely governed by the $\langle ϕ\rangle$ distribution, studying this distribution provides a new handle for benchmarking and constraining the modeling of edge effects in heavy-ion event generators.
title Living on the edge: radius effects in the angular substructure of heavy-ion jets
topic High Energy Physics - Phenomenology
High Energy Physics - Experiment
Nuclear Experiment
Nuclear Theory
url https://arxiv.org/abs/2512.10026