Dataset

GSI-2023-00189

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Measurement of the groomed jet radius and momentum splitting fraction in pp and Pb$-$Pb collisions at $\sqrt{s_{NN}} = 5.02$ TeV

A Large Ion Collider Experiment Collaboration ; ALICE Collaboration (Corresponding author)

2022

Please use a persistent id in citations: doi:10.17182/HEPDATA.128137

Abstract: This article presents groomed jet substructure measurements in pp and Pb-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV with the ALICE detector. The soft drop grooming algorithm provides access to the hard parton splittings inside a jet by removing soft wide-angle radiation. We report the groomed jet momentum splitting fraction, zg, and the (scaled) groomed jet radius, θg. Charged-particle jets are reconstructed at midrapidity using the anti-k$_T$ algorithm with resolution parameters R = 0.2 and R = 0.4. In heavy-ion collisions, the large underlying event poses a challenge for the reconstruction of groomed jet observables, since fluctuations in the background can cause groomed parton splittings to be misidentified. By using strong grooming conditions to reduce this background, we report these observables fully corrected for detector effects and background fluctuations for the first time. A narrowing of the θg distribution in Pb-Pb collisions compared to pp collisions is seen, which provides direct evidence of the modification of the angular structure of jets in the quark-gluon plasma. No significant modification of the zg distribution in Pb-Pb collisions compared to pp collisions is observed. These results are compared with a variety of theoretical models of jet quenching, and provide constraints on jet energy-loss mechanisms and coherence effects in the quark-gluon plasma.

Note: Journal Article GSI record: GSI-2023-00151

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Contributing Institute(s):

1. ALICE (ALI)
2. Detektorlabor (DTL)
3. IT (CIT)
4. ExtreMe Matter Institute, EMMI (EXM)
5. Collaboration CERN: ALICE (ALICE@CERN)

Research Program(s):

1. 612 - Cosmic Matter in the Laboratory (POF4-612) (POF4-612)
2. HGS-HIRe - HGS-HIRe for FAIR (HGS-HIRe) (HGS-HIRe)
3. SUC-GSI-Heidelberg - Strategic university cooperation GSI-U Heidelberg (SUC-GSI-HE) (SUC-GSI-HE)
4. SUC-GSI-Frankfurt - Strategic university cooperation GSI-U Frankfurt/M (SUC-GSI-FR) (SUC-GSI-FR)
5. SUC-GSI-Darmstadt - Strategic university cooperation GSI-TU Darmstadt (SUC-GSI-DA) (SUC-GSI-DA)

Experiment(s):

1. LHC: ALICE

Appears in the scientific report 2022

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Linked articles:

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Journal Article Acharya, S. ; Adamova, D. ; Adler, A. ; et al
Measurement of the groomed jet radius and momentum splitting fraction in pp and Pb$-$Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV
Physical review letters 128(10), 102001 (2022) [10.1103/PhysRevLett.128.102001]2022   Files  Fulltext by arXiv.org BibTeX | EndNote: XML, Text | RIS

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