Detection of the characteristic pion-decay signature in supernova remnants

Cosmic rays are particles (mostly protons) accelerated to relativistic speeds. Despite wide agreement that supernova remnants (SNRs) are the sources of galactic cosmic rays, unequivocal evidence for the acceleration of protons in these objects is still lacking. When accelerated protons encounter int...

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Autor principal: Ackermann, M.
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Acceso en línea:http://hdl.handle.net/20.500.12110/paper_00368075_v339_n6121_p807_Ackermann
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spelling todo:paper_00368075_v339_n6121_p807_Ackermann2023-10-03T14:47:54Z Detection of the characteristic pion-decay signature in supernova remnants Ackermann, M. proton cosmic ray detection method electron extraterrestrial matter scattering acceleration article brems radiation compton effect cosmic radiation electron energy gamma radiation infrared radiation pion priority journal radioisotope decay synchrotron radiation telescope Cosmic rays are particles (mostly protons) accelerated to relativistic speeds. Despite wide agreement that supernova remnants (SNRs) are the sources of galactic cosmic rays, unequivocal evidence for the acceleration of protons in these objects is still lacking. When accelerated protons encounter interstellar material, they produce neutral pions, which in turn decay into gamma rays. This offers a compelling way to detect the acceleration sites of protons. The identification of pion-decay gamma rays has been difficult because high-energy electrons also produce gamma rays via bremsstrahlung and inverse Compton scattering. We detected the characteristic pion-decay feature in the gamma-ray spectra of two SNRs, IC 443 and W44, with the Fermi Large Area Telescope. This detection provides direct evidence that cosmic-ray protons are accelerated in SNRs. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00368075_v339_n6121_p807_Ackermann
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic proton
cosmic ray
detection method
electron
extraterrestrial matter
scattering
acceleration
article
brems radiation
compton effect
cosmic radiation
electron
energy
gamma radiation
infrared radiation
pion
priority journal
radioisotope decay
synchrotron radiation
telescope
spellingShingle proton
cosmic ray
detection method
electron
extraterrestrial matter
scattering
acceleration
article
brems radiation
compton effect
cosmic radiation
electron
energy
gamma radiation
infrared radiation
pion
priority journal
radioisotope decay
synchrotron radiation
telescope
Ackermann, M.
Detection of the characteristic pion-decay signature in supernova remnants
topic_facet proton
cosmic ray
detection method
electron
extraterrestrial matter
scattering
acceleration
article
brems radiation
compton effect
cosmic radiation
electron
energy
gamma radiation
infrared radiation
pion
priority journal
radioisotope decay
synchrotron radiation
telescope
description Cosmic rays are particles (mostly protons) accelerated to relativistic speeds. Despite wide agreement that supernova remnants (SNRs) are the sources of galactic cosmic rays, unequivocal evidence for the acceleration of protons in these objects is still lacking. When accelerated protons encounter interstellar material, they produce neutral pions, which in turn decay into gamma rays. This offers a compelling way to detect the acceleration sites of protons. The identification of pion-decay gamma rays has been difficult because high-energy electrons also produce gamma rays via bremsstrahlung and inverse Compton scattering. We detected the characteristic pion-decay feature in the gamma-ray spectra of two SNRs, IC 443 and W44, with the Fermi Large Area Telescope. This detection provides direct evidence that cosmic-ray protons are accelerated in SNRs.
format JOUR
author Ackermann, M.
author_facet Ackermann, M.
author_sort Ackermann, M.
title Detection of the characteristic pion-decay signature in supernova remnants
title_short Detection of the characteristic pion-decay signature in supernova remnants
title_full Detection of the characteristic pion-decay signature in supernova remnants
title_fullStr Detection of the characteristic pion-decay signature in supernova remnants
title_full_unstemmed Detection of the characteristic pion-decay signature in supernova remnants
title_sort detection of the characteristic pion-decay signature in supernova remnants
url http://hdl.handle.net/20.500.12110/paper_00368075_v339_n6121_p807_Ackermann
work_keys_str_mv AT ackermannm detectionofthecharacteristicpiondecaysignatureinsupernovaremnants
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