FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE SUPERNOVA REMNANT G8.7-0.1
Abstract
We present a detailed analysis of the GeV gamma-ray emission toward the supernova remnant (SNR) G8.7-0.1 with the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope. An investigation of the relationship between G8.7-0.1 and the TeV unidentified source HESS J1804-216 provides us with an important clue on diffusion process of cosmic rays if particle acceleration operates in the SNR. The GeV gamma-ray emission is extended with most of the emission in positional coincidence with the SNR G8.7-0.1 and a lesser part located outside the western boundary of G8.7-0.1. The region of the gamma-ray emission overlaps spatially connected molecular clouds, implying a physical connection for the gamma-ray structure. The total gamma-ray spectrum measured with LAT from 200 MeV-100 GeV can be described by a broken power-law function with a break of 2.4 {+-} 0.6 (stat) {+-} 1.2 (sys) GeV, and photon indices of 2.10 {+-} 0.06 (stat) {+-} 0.10 (sys) below the break and 2.70 {+-} 0.12 (stat) {+-} 0.14 (sys) above the break. Given the spatial association among the gamma rays, the radio emission of G8.7-0.1, and the molecular clouds, the decay of {pi}{sup 0}s produced by particles accelerated in the SNR and hitting the molecular cloudsmore »
- Authors:
-
- W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States)
- Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, I-56127 Pisa (Italy)
- Laboratoire AIM, CEA-IRFU/CNRS/Universite Paris Diderot, Service d'Astrophysique, CEA Saclay, 91191 Gif sur Yvette (France)
- Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, I-34127 Trieste (Italy)
- Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131 Padova (Italy)
- Istituto Nazionale di Fisica Nucleare, Sezione di Perugia, I-06123 Perugia (Italy)
- Dipartimento di Fisica 'M. Merlin' dell'Universita e del Politecnico di Bari, I-70126 Bari (Italy)
- Laboratoire Leprince-Ringuet, Ecole polytechnique, CNRS/IN2P3, Palaiseau (France)
- Publication Date:
- OSTI Identifier:
- 22004318
- Resource Type:
- Journal Article
- Journal Name:
- Astrophysical Journal
- Additional Journal Information:
- Journal Volume: 744; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCELERATION; ASTROPHYSICS; COSMIC RADIATION; ENERGY DEPENDENCE; GAMMA RADIATION; GAMMA SPECTRA; MORPHOLOGY; SUPERNOVA REMNANTS; TELESCOPES; TEV RANGE
Citation Formats
Ajello, M, Allafort, A, Bechtol, K, Berenji, B, Blandford, R D, Bloom, E D, Borgland, A W, Buehler, R, Cameron, R A, Baldini, L, Bellazzini, R, Bregeon, J, Ballet, J, Barbiellini, G, Bastieri, D, Buson, S, Bonamente, E, Brigida, M, Bruel, P, Caliandro, G. A., E-mail: hanabata@hep01.hepl.hiroshima-u.ac.jp, E-mail: katagiri@mx.ibaraki.ac.jp, and others, and. FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE SUPERNOVA REMNANT G8.7-0.1. United States: N. p., 2012.
Web. doi:10.1088/0004-637X/744/1/80.
Ajello, M, Allafort, A, Bechtol, K, Berenji, B, Blandford, R D, Bloom, E D, Borgland, A W, Buehler, R, Cameron, R A, Baldini, L, Bellazzini, R, Bregeon, J, Ballet, J, Barbiellini, G, Bastieri, D, Buson, S, Bonamente, E, Brigida, M, Bruel, P, Caliandro, G. A., E-mail: hanabata@hep01.hepl.hiroshima-u.ac.jp, E-mail: katagiri@mx.ibaraki.ac.jp, & others, and. FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE SUPERNOVA REMNANT G8.7-0.1. United States. https://doi.org/10.1088/0004-637X/744/1/80
Ajello, M, Allafort, A, Bechtol, K, Berenji, B, Blandford, R D, Bloom, E D, Borgland, A W, Buehler, R, Cameron, R A, Baldini, L, Bellazzini, R, Bregeon, J, Ballet, J, Barbiellini, G, Bastieri, D, Buson, S, Bonamente, E, Brigida, M, Bruel, P, Caliandro, G. A., E-mail: hanabata@hep01.hepl.hiroshima-u.ac.jp, E-mail: katagiri@mx.ibaraki.ac.jp, and others, and. 2012.
"FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE SUPERNOVA REMNANT G8.7-0.1". United States. https://doi.org/10.1088/0004-637X/744/1/80.
@article{osti_22004318,
title = {FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE SUPERNOVA REMNANT G8.7-0.1},
author = {Ajello, M and Allafort, A and Bechtol, K and Berenji, B and Blandford, R D and Bloom, E D and Borgland, A W and Buehler, R and Cameron, R A and Baldini, L and Bellazzini, R and Bregeon, J and Ballet, J and Barbiellini, G and Bastieri, D and Buson, S and Bonamente, E and Brigida, M and Bruel, P and Caliandro, G. A., E-mail: hanabata@hep01.hepl.hiroshima-u.ac.jp, E-mail: katagiri@mx.ibaraki.ac.jp and others, and},
abstractNote = {We present a detailed analysis of the GeV gamma-ray emission toward the supernova remnant (SNR) G8.7-0.1 with the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope. An investigation of the relationship between G8.7-0.1 and the TeV unidentified source HESS J1804-216 provides us with an important clue on diffusion process of cosmic rays if particle acceleration operates in the SNR. The GeV gamma-ray emission is extended with most of the emission in positional coincidence with the SNR G8.7-0.1 and a lesser part located outside the western boundary of G8.7-0.1. The region of the gamma-ray emission overlaps spatially connected molecular clouds, implying a physical connection for the gamma-ray structure. The total gamma-ray spectrum measured with LAT from 200 MeV-100 GeV can be described by a broken power-law function with a break of 2.4 {+-} 0.6 (stat) {+-} 1.2 (sys) GeV, and photon indices of 2.10 {+-} 0.06 (stat) {+-} 0.10 (sys) below the break and 2.70 {+-} 0.12 (stat) {+-} 0.14 (sys) above the break. Given the spatial association among the gamma rays, the radio emission of G8.7-0.1, and the molecular clouds, the decay of {pi}{sup 0}s produced by particles accelerated in the SNR and hitting the molecular clouds naturally explains the GeV gamma-ray spectrum. We also find that the GeV morphology is not well represented by the TeV emission from HESS J1804-216 and that the spectrum in the GeV band is not consistent with the extrapolation of the TeV gamma-ray spectrum. The spectral index of the TeV emission is consistent with the particle spectral index predicted by a theory that assumes energy-dependent diffusion of particles accelerated in an SNR. We discuss the possibility that the TeV spectrum originates from the interaction of particles accelerated in G8.7-0.1 with molecular clouds, and we constrain the diffusion coefficient of the particles.},
doi = {10.1088/0004-637X/744/1/80},
url = {https://www.osti.gov/biblio/22004318},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 1,
volume = 744,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2012},
month = {Sun Jan 01 00:00:00 EST 2012}
}