Evidence of X-Ray Synchrotron Emission from Electrons Accelerated to 40 T[CLC]e[/CLC]V in the Supernova Remnant Cassiopeia A
| Autor: | Richard E. Lingenfelter, Eric V. Gotthelf, Jonathan W. Keohane, Richard E. Rothschild, William A. Heindl, Duane Gruber, Michael R. Pelling, G. E. Allen, Keith Jahoda, Robert Petre, Philip Blanco, D. Marsden |
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| Rok vydání: | 1997 |
| Předmět: |
Physics
Photon Astrophysics::High Energy Astrophysical Phenomena Astrophysics (astro-ph) FOS: Physical sciences Proportional counter Synchrotron radiation Astronomy and Astrophysics Cosmic ray Astrophysics::Cosmology and Extragalactic Astrophysics Electron Astrophysics Cassiopeia A Supernova Space and Planetary Science Supernova remnant Astrophysics::Galaxy Astrophysics |
| Zdroj: | Scopus-Elsevier |
| ISSN: | 0004-637X |
| Popis: | We present the 2-60 keV spectrum of the supernova remnant Cassiopeia A measured using the Proportional Counter Array and the High Energy X-ray Timing Experiment on the Rossi X-ray Timing Explorer satellite. In addition to the previously reported strong emission-line features produced by thermal plasmas, the broad-band spectrum has a high-energy "tail" that extends to energies at least as high as 120 keV. This tail may be described by a broken power law that has photon indices of 1.8 +0.5/-0.6 and 3.04 +0.15/-0.13 and a break energy of 15.9 +0.3/-0.4 keV. We argue that the high-energy component, which dominates the spectrum above about 10 keV, is produced by synchrotron radiation from electrons that have energies up to at least 40 TeV. This conclusion supports the hypothesis that Galactic cosmic rays are accelerated predominantly in supernova remnants. 10 pages of text, 3 figures, accepted for Astrophys. J. Letters |
| Databáze: | OpenAIRE |
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