TY - JOUR
T1 - Measurement of the nuclear modification factor of b-jets in 5.02 TeV Pb+Pb collisions with the ATLAS detector
AU - ATLAS Collaboration
AU - Allport, Phil
AU - Auriol, Adrien
AU - Bellos, Panagiotis
AU - Bird, Gareth
AU - Bracinik, Juraj
AU - Charlton, David
AU - Chisholm, Andrew
AU - Cooke, Harry
AU - Fitschen, Tobias
AU - Freeman, Patrick
AU - George, William
AU - Gonella, Laura
AU - Hawkes, Chris
AU - Hillier, Stephen
AU - Kempster, Jacob
AU - Lewis, Daniel
AU - Marinescu, Mihaela
AU - Mendes Jacques Da Costa, Antonio Manuel
AU - Neep, Thomas
AU - Newman, Paul
AU - Nikolopoulos, Konstantinos
AU - Cardoso Silva, Júlia
AU - Stampekis, Alexis
AU - Thomas, Jurgen
AU - Thompson, Paul
AU - Virdee, Gov
AU - Ward, Robert
AU - Watson, Alan
AU - Watson, Miriam
PY - 2023/5/25
Y1 - 2023/5/25
N2 - This paper presents a measurement of b-jet production in Pb+Pb and pp collisions at √SNN=5.02 TeV with the ATLAS detector at the LHC. The measurement uses 260 pb−1 of pp collisions collected in 2017 and 1.4 nb−1 of Pb+Pb collisions collected in 2018. In both collision systems, jets are reconstructed via the anti-kt algorithm. The b-jets are identified from a sample of jets containing muons from the semileptonic decay of b-quarks using template fits of the muon momentum relative to the jet axis. In pp collisions, b-jets are reconstructed for radius parameters R= 0.2 and R= 0.4, and only R= 0.2 jets are used in Pb+Pb collisions. For comparison, inclusive R= 0.2 jets are also measured using 1.7 nb−1 of Pb+Pb collisions collected in 2018 and the same pp collision data as the b-jet measurement. The nuclear modification factor, RAA, is calculated for both b-jets and inclusive jets with R= 0.2 over the transverse momentum range of 80--290 GeV. The nuclear modification factor for b-jets decreases from peripheral to central collisions. The ratio of the b-jet RAA to inclusive jet RAA is also presented and suggests that the RAA for b-jets is larger than that for inclusive jets in central Pb+Pb collisions. The measurements are compared with theoretical calculations and suggest a role for mass and colour-charge effects in partonic energy loss in heavy-ion collisions.
AB - This paper presents a measurement of b-jet production in Pb+Pb and pp collisions at √SNN=5.02 TeV with the ATLAS detector at the LHC. The measurement uses 260 pb−1 of pp collisions collected in 2017 and 1.4 nb−1 of Pb+Pb collisions collected in 2018. In both collision systems, jets are reconstructed via the anti-kt algorithm. The b-jets are identified from a sample of jets containing muons from the semileptonic decay of b-quarks using template fits of the muon momentum relative to the jet axis. In pp collisions, b-jets are reconstructed for radius parameters R= 0.2 and R= 0.4, and only R= 0.2 jets are used in Pb+Pb collisions. For comparison, inclusive R= 0.2 jets are also measured using 1.7 nb−1 of Pb+Pb collisions collected in 2018 and the same pp collision data as the b-jet measurement. The nuclear modification factor, RAA, is calculated for both b-jets and inclusive jets with R= 0.2 over the transverse momentum range of 80--290 GeV. The nuclear modification factor for b-jets decreases from peripheral to central collisions. The ratio of the b-jet RAA to inclusive jet RAA is also presented and suggests that the RAA for b-jets is larger than that for inclusive jets in central Pb+Pb collisions. The measurements are compared with theoretical calculations and suggest a role for mass and colour-charge effects in partonic energy loss in heavy-ion collisions.
U2 - 10.1140/epjc/s10052-023-11427-9
DO - 10.1140/epjc/s10052-023-11427-9
M3 - Article
SN - 1434-6044
VL - 83
JO - European Physical Journal C
JF - European Physical Journal C
IS - 5
M1 - 438
ER -