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Title: Model studies of fluctuations in the background for jets in heavy ion collisions

Abstract

Jets produced in high energy heavy ion collisions are quenched by the quark gluon plasma. Measurements of these jets are influenced by the methods used to suppress and subtract the large, fluctuating background and the assumptions inherent in these methods. We compare the measurements of the background in Pb+Pb collisions at √sNN = 2.76 TeV by the ALICE Collaboration (Abelev et al., J. High Energy Phys. 03 (2012) 053) to calculations in TENNGEN (a data-driven random background generator) and PYTHIA ANGANTYR . A detailed understanding of the width of these fluctuations is important for reducing uncertainties due to unfolding and extending measurements to lower momenta and larger resolution parameters. The standard deviation of the energy in random cones in TENNGEN is approximately in agreement with the form predicted in the ALICE paper, with deviations of 1–6%. The standard deviation of energy in random cones in ANGANTYR exceeds the same predictions by approximately 13%. Deviations in both models can be explained by the assumption that the single particle d2N/dy d pT is a gamma distribution in the derivation of the prediction, whereas the model uses a different distribution. This indicates that model comparisons are potentially sensitive to the treatment of themore » background. We demonstrate that unfolding methods used to remove background fluctuations from jets can affect the comparisons between models and data, even in the absence of detector effects. Our findings suggest the need to more carefully consider methods for comparing simulations and data.« less

Authors:
ORCiD logo; ORCiD logo; ORCiD logo
Publication Date:
Research Org.:
Univ. of Tennessee, Knoxville, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP); National Science Foundation (NSF)
Contributing Org.:
Joint Institute for Computational Sciences
OSTI Identifier:
1896319
Alternate Identifier(s):
OSTI ID: 1895608
Grant/Contract Number:  
FG02-96ER40982; OAC-1550300
Resource Type:
Published Article
Journal Name:
Physical Review C
Additional Journal Information:
Journal Name: Physical Review C Journal Volume: 106 Journal Issue: 4; Journal ID: ISSN 2469-9985
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 97 MATHEMATICS AND COMPUTING; Jets & heavy flavor physics; Particle correlations and fluctuations; Relativistic heavy ion collisions; Monte Carlo methods

Citation Formats

Hughes, Charles, da Silva, Antonio Carlos Oliveira, and Nattrass, Christine. Model studies of fluctuations in the background for jets in heavy ion collisions. United States: N. p., 2022. Web. doi:10.1103/PhysRevC.106.044915.
Hughes, Charles, da Silva, Antonio Carlos Oliveira, & Nattrass, Christine. Model studies of fluctuations in the background for jets in heavy ion collisions. United States. https://doi.org/10.1103/PhysRevC.106.044915
Hughes, Charles, da Silva, Antonio Carlos Oliveira, and Nattrass, Christine. Mon . "Model studies of fluctuations in the background for jets in heavy ion collisions". United States. https://doi.org/10.1103/PhysRevC.106.044915.
@article{osti_1896319,
title = {Model studies of fluctuations in the background for jets in heavy ion collisions},
author = {Hughes, Charles and da Silva, Antonio Carlos Oliveira and Nattrass, Christine},
abstractNote = {Jets produced in high energy heavy ion collisions are quenched by the quark gluon plasma. Measurements of these jets are influenced by the methods used to suppress and subtract the large, fluctuating background and the assumptions inherent in these methods. We compare the measurements of the background in Pb+Pb collisions at √sNN = 2.76 TeV by the ALICE Collaboration (Abelev et al., J. High Energy Phys. 03 (2012) 053) to calculations in TENNGEN (a data-driven random background generator) and PYTHIA ANGANTYR . A detailed understanding of the width of these fluctuations is important for reducing uncertainties due to unfolding and extending measurements to lower momenta and larger resolution parameters. The standard deviation of the energy in random cones in TENNGEN is approximately in agreement with the form predicted in the ALICE paper, with deviations of 1–6%. The standard deviation of energy in random cones in ANGANTYR exceeds the same predictions by approximately 13%. Deviations in both models can be explained by the assumption that the single particle d2N/dy d pT is a gamma distribution in the derivation of the prediction, whereas the model uses a different distribution. This indicates that model comparisons are potentially sensitive to the treatment of the background. We demonstrate that unfolding methods used to remove background fluctuations from jets can affect the comparisons between models and data, even in the absence of detector effects. Our findings suggest the need to more carefully consider methods for comparing simulations and data.},
doi = {10.1103/PhysRevC.106.044915},
journal = {Physical Review C},
number = 4,
volume = 106,
place = {United States},
year = {Mon Oct 31 00:00:00 EDT 2022},
month = {Mon Oct 31 00:00:00 EDT 2022}
}

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