Systematic study of the uncertainties in fitting the cosmic positron data by AMS02
Abstract
The operation of AMS02 opens a new era for the study of cosmic ray physics with unprecedentedly precise data which are comparable with the laboratory measurements. The high precision data allow a quantitative study on the cosmic ray physics and give strict constraints on the nature of cosmic ray sources. However, the intrinsic errors from the theoretical models to interpret the data become dominant over the errors in the data. In the present work we try to give a systematic study on the uncertainties of the models to explain the AMS02 positron fraction data, which shows the cosmic ray e{sup +}e{sup −} excesses together with the PAMELA and FermiLAT measurements. The excesses can be attributed to contributions from the extra e{sup +}e{sup −} sources, such as pulsars or the dark matter annihilation. The possible systematic uncertainties of the theoretical models considered include the cosmic ray propagation, the treatment of the low energy data, the solar modulation, the pp interaction models, the nuclei injection spectrum and so on. We find that in general a spectral hardening of the primary electron injection spectrum above ∼50–100 GeV is favored by the data. Furthermore, the present model uncertainties may lead to a factor ofmore »
 Authors:
 Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)
 Publication Date:
 OSTI Identifier:
 22525938
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 03; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; ANNIHILATION; COMPARATIVE EVALUATIONS; COSMIC RAY PROPAGATION; COSMIC RAY SOURCES; ELECTRON BEAM INJECTION; ELECTRONPOSITRON INTERACTIONS; ERRORS; GEV RANGE; MASS; MODULATION; NONLUMINOUS MATTER; PROTONPROTON INTERACTIONS; PULSARS; SPECTRAL HARDENING
Citation Formats
Yuan, Qiang, and Bi, XiaoJun, Email: yuanq@ihep.ac.cn, Email: bixj@ihep.ac.cn. Systematic study of the uncertainties in fitting the cosmic positron data by AMS02. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/03/033.
Yuan, Qiang, & Bi, XiaoJun, Email: yuanq@ihep.ac.cn, Email: bixj@ihep.ac.cn. Systematic study of the uncertainties in fitting the cosmic positron data by AMS02. United States. doi:10.1088/14757516/2015/03/033.
Yuan, Qiang, and Bi, XiaoJun, Email: yuanq@ihep.ac.cn, Email: bixj@ihep.ac.cn. 2015.
"Systematic study of the uncertainties in fitting the cosmic positron data by AMS02". United States.
doi:10.1088/14757516/2015/03/033.
@article{osti_22525938,
title = {Systematic study of the uncertainties in fitting the cosmic positron data by AMS02},
author = {Yuan, Qiang and Bi, XiaoJun, Email: yuanq@ihep.ac.cn, Email: bixj@ihep.ac.cn},
abstractNote = {The operation of AMS02 opens a new era for the study of cosmic ray physics with unprecedentedly precise data which are comparable with the laboratory measurements. The high precision data allow a quantitative study on the cosmic ray physics and give strict constraints on the nature of cosmic ray sources. However, the intrinsic errors from the theoretical models to interpret the data become dominant over the errors in the data. In the present work we try to give a systematic study on the uncertainties of the models to explain the AMS02 positron fraction data, which shows the cosmic ray e{sup +}e{sup −} excesses together with the PAMELA and FermiLAT measurements. The excesses can be attributed to contributions from the extra e{sup +}e{sup −} sources, such as pulsars or the dark matter annihilation. The possible systematic uncertainties of the theoretical models considered include the cosmic ray propagation, the treatment of the low energy data, the solar modulation, the pp interaction models, the nuclei injection spectrum and so on. We find that in general a spectral hardening of the primary electron injection spectrum above ∼50–100 GeV is favored by the data. Furthermore, the present model uncertainties may lead to a factor of ∼2 enlargement in the determination of the parameter regions of the extra source, such as the dark matter mass, annihilation rate and so on.},
doi = {10.1088/14757516/2015/03/033},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 03,
volume = 2015,
place = {United States},
year = 2015,
month = 3
}

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