Measurement of inclusive and leading subjet fragmentation in pp and Pb-Pb collisions at root sNN=5.02 TeV

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21340%2F23%3A00368617" target="_blank" >RIV/68407700:21340/23:00368617 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1007/JHEP05(2023)245" target="_blank" >https://doi.org/10.1007/JHEP05(2023)245</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/JHEP05(2023)245" target="_blank" >10.1007/JHEP05(2023)245</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Measurement of inclusive and leading subjet fragmentation in pp and Pb-Pb collisions at root sNN=5.02 TeV

Popis výsledku v původním jazyce

This article presents new measurements of the fragmentation properties of jets in both proton-proton (pp) and heavy-ion collisions with the ALICE experiment at the Large Hadron Collider (LHC). We report distributions of the fraction z(r) of transverse momentum carried by subjets of radius r within jets of radius R. Charged-particle jets are reconstructed at midrapidity using the anti-k(T) algorithm with jet radius R = 0.4, and subjets are reconstructed by reclustering the jet constituents using the anti-k(T) algorithm with radii r = 0.1 and r = 0.2. In proton-proton collisions, we measure both the inclusive and leading subjet distributions. We compare these measurements to perturbative calculations at next-to-leading logarithmic accuracy, which suggest a large impact of threshold resummation and hadronization effects on the z(r) distribution. In heavy-ion collisions, we measure the leading subjet distributions, which allow access to a region of harder jet frag- mentation than has been probed by previous measurements of jet quenching via hadron fragmentation distributions. The z(r) distributions enable extraction of the parton-to-subjet fragmentation function and allow for tests of the universality of jet fragmentation functions in the quark-gluon plasma (QGP). We find no significant modification of z(r) distributions in Pb-Pb compared to pp collisions. However, the distributions are also consistent with a hardening trend for z(r)< 0.95, as predicted by several jet quenching models. As z(r) -> 1 our results indicate that any such hardening effects cease, exposing qualitatively new possibilities to disentangle competing jet quenching mechanisms. By comparing our results to theoretical calculations based on an independent extraction of the parton-to-jet fragmentation function, we find consistency with the universality of jet fragmentation and no indication of factorization breaking in the QGP.

Název v anglickém jazyce

Measurement of inclusive and leading subjet fragmentation in pp and Pb-Pb collisions at root sNN=5.02 TeV

Popis výsledku anglicky

This article presents new measurements of the fragmentation properties of jets in both proton-proton (pp) and heavy-ion collisions with the ALICE experiment at the Large Hadron Collider (LHC). We report distributions of the fraction z(r) of transverse momentum carried by subjets of radius r within jets of radius R. Charged-particle jets are reconstructed at midrapidity using the anti-k(T) algorithm with jet radius R = 0.4, and subjets are reconstructed by reclustering the jet constituents using the anti-k(T) algorithm with radii r = 0.1 and r = 0.2. In proton-proton collisions, we measure both the inclusive and leading subjet distributions. We compare these measurements to perturbative calculations at next-to-leading logarithmic accuracy, which suggest a large impact of threshold resummation and hadronization effects on the z(r) distribution. In heavy-ion collisions, we measure the leading subjet distributions, which allow access to a region of harder jet frag- mentation than has been probed by previous measurements of jet quenching via hadron fragmentation distributions. The z(r) distributions enable extraction of the parton-to-subjet fragmentation function and allow for tests of the universality of jet fragmentation functions in the quark-gluon plasma (QGP). We find no significant modification of z(r) distributions in Pb-Pb compared to pp collisions. However, the distributions are also consistent with a hardening trend for z(r)< 0.95, as predicted by several jet quenching models. As z(r) -> 1 our results indicate that any such hardening effects cease, exposing qualitatively new possibilities to disentangle competing jet quenching mechanisms. By comparing our results to theoretical calculations based on an independent extraction of the parton-to-jet fragmentation function, we find consistency with the universality of jet fragmentation and no indication of factorization breaking in the QGP.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10303 - Particles and field physics

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of High Energy Physics

ISSN

1029-8479

e-ISSN

1029-8479

Svazek periodika

2023

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

IT - Italská republika

Počet stran výsledku

34

Strana od-do

—

Kód UT WoS článku

001022895100001

EID výsledku v databázi Scopus

2-s2.0-85161037786