First measurements of N-subjettiness in central Pb-Pb collisions at p root s(NN)=2.76 TeV
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378271%3A_____%2F21%3A00547017" target="_blank" >RIV/68378271:_____/21:00547017 - isvavai.cz</a>
Alternative codes found
RIV/61389005:_____/21:00547017 RIV/68407700:21340/21:00352407
Result on the web
<a href="https://doi.org/10.1007/JHEP10(2021)003" target="_blank" >https://doi.org/10.1007/JHEP10(2021)003</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1007/JHEP10(2021)003" target="_blank" >10.1007/JHEP10(2021)003</a>
Alternative languages
Result language
angličtina
Original language name
First measurements of N-subjettiness in central Pb-Pb collisions at p root s(NN)=2.76 TeV
Original language description
The ALICE Collaboration reports the first fully-corrected measurements of the N-subjettiness observable for track-based jets in heavy-ion collisions. This study is performed using data recorded in pp and Pb-Pb collisions at centre-of-mass energies of root s = 7 TeV and root s(NN) = 2.76 TeV, respectively. In particular the ratio of 2-subjettiness to 1-subjettiness, tau(2)/tau(1), which is sensitive to the rate of two-pronged jet substructure, is presented. Energy loss of jets traversing the strongly interacting medium in heavy-ion collisions is expected to change the rate of two-pronged substructure relative to vacuum. The results are presented for jets with a resolution parameter of R = 0.4 and charged jet transverse momentum of 40 <= p(T,jet) <= 60 GeV/c, which constitute a larger jet resolution and lower jet transverse momentum interval than previous measurements in heavy-ion collisions. This has been achieved by utilising a semi-inclusive hadron-jet coincidence technique to suppress the larger jet combinatorial background in this kinematic region. No significant modification of the tau(2)/tau(1) observable for track-based jets in Pb-Pb collisions is observed relative to vacuum PYTHIA6 and PYTHIA8 references at the same collision energy. The measurements of tau(2)/tau(1), together with the splitting aperture angle increment R, are also performed in pp collisions at root s = 7 TeV for inclusive jets. These results are compared with PYTHIA calculations at root s = 7 TeV, in order to validate the model as a vacuum reference for the Pb-Pb centre-of-mass energy. The PYTHIA references for tau(2)/tau(1) are shifted to larger values compared to the measurement in pp collisions. This hints at a reduction in the rate of two-pronged jets in Pb-Pb collisions compared to pp collisions.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10303 - Particles and field physics
Result continuities
Project
Result was created during the realization of more than one project. More information in the Projects tab.
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2021
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Journal of High Energy Physics
ISSN
1029-8479
e-ISSN
1029-8479
Volume of the periodical
2021
Issue of the periodical within the volume
10
Country of publishing house
US - UNITED STATES
Number of pages
34
Pages from-to
003
UT code for WoS article
000703983100001
EID of the result in the Scopus database
2-s2.0-85116808987