Ústav technické a experimentální fyziky Institute of Experimental and Applied Physics

Measurement of jet fragmentation in Pb plus Pb and pp collisions at root S-NN=5.02 TeV with the ATLAS detector

NázevTitle
Measurement of jet fragmentation in Pb plus Pb and pp collisions at root S-NN=5.02 TeV with the ATLAS detectorMeasurement of jet fragmentation in Pb plus Pb and pp collisions at root S-NN=5.02 TeV with the ATLAS detector
Druh výsledkuResult type
Článek v časopiseJournal article
AutořiAuthors
M. Aaboud, G. Aad, B. Abbott, O. Abdinov, B. Ali, K. Augsten, D. Caforio, P. Gallus, M. Havránek, Z. Hubáček, M. Myška, R. Novotný, S. Pospíšil, T. Slavíček, K. Smolek, M. Solar, A. Sopczak, M. Suk, V. Vacek, P. Vokáč, V. Vrba
DOIDOI
10.1103/PhysRevC.98.024908
Časopis / citaceJournal / citation
PHYSICAL REVIEW C. 2018, 98(2), ISSN 2469-9985.
RokYear
2018
JazykLanguage
eng
WoSWoS
000441857800002
ScopusScopus
2-s2.0-85052533784
RIVRIV
RIV/68407700:21220/18:00329549!RIV19-MSM-21220___
ProjektProject
Získávání nových poznatků o mikrosvětě v infrastruktuře CERNAcquiring new pieces of knowledge about micro-world in CERN research infrastructure

AbstraktAbstract

This paper presents a measurement of jet fragmentation functions in 0.49 nb(-1) of Pb +Pb collisions and 25 pb(-1) of pp collisions at root S-NN = 5.02 TeV collected in 2015 with the ATLAS detector at the LHC. These measurements provide insight into the jet quenching process in the quark-gluon plasma created in the aftermath of ultrarelativistic collisions between two nuclei. The modifications to the jet fragmentation functions are quantified by dividing the measurements in Pb+Pb collisions by baseline measurements in pp collisions. This ratio is studied as a function of the transverse momentum of the jet, the jet rapidity, and the centrality of the collision. In both collision systems, the jet fragmentation functions are measured for jets with transverse momentum between 126 and 398 GeV and with an absolute value of jet rapidity less than 2.1. An enhancement of particles carrying a small fraction of the jet momentum is observed, which increases with centrality and with increasing jet transverse momentum. Yields of particles carrying a very large fraction of the jet momentum are also observed to be enhanced. Between these two enhancements of the fragmentation functions a suppression of particles carrying an intermediate fraction of the jet momentum is observed in Pb+Pb collisions. A small dependence of the modifications on jet rapidity is observed.

This paper presents a measurement of jet fragmentation functions in 0.49 nb(-1) of Pb +Pb collisions and 25 pb(-1) of pp collisions at root S-NN = 5.02 TeV collected in 2015 with the ATLAS detector at the LHC. These measurements provide insight into the jet quenching process in the quark-gluon plasma created in the aftermath of ultrarelativistic collisions between two nuclei. The modifications to the jet fragmentation functions are quantified by dividing the measurements in Pb+Pb collisions by baseline measurements in pp collisions. This ratio is studied as a function of the transverse momentum of the jet, the jet rapidity, and the centrality of the collision. In both collision systems, the jet fragmentation functions are measured for jets with transverse momentum between 126 and 398 GeV and with an absolute value of jet rapidity less than 2.1. An enhancement of particles carrying a small fraction of the jet momentum is observed, which increases with centrality and with increasing jet transverse momentum. Yields of particles carrying a very large fraction of the jet momentum are also observed to be enhanced. Between these two enhancements of the fragmentation functions a suppression of particles carrying an intermediate fraction of the jet momentum is observed in Pb+Pb collisions. A small dependence of the modifications on jet rapidity is observed.