Evidence of X-Ray Synchrotron Emission from Electrons Accelerated to 40 T[CLC]e[/CLC]V in the Supernova Remnant Cassiopeia A
Open Access
- 20 September 1997
- journal article
- research article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 487 (1), L97-L100
- https://doi.org/10.1086/310878
Abstract
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 broadband 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 Γ1 = 1.8+ 0.5−0.6 and Γ2 = 3.04+ 0.15−0.13 and a break energy of Eb = 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.Keywords
This publication has 17 references indexed in Scilit:
- Classified AdvertisingJournal of Occupational and Environmental Medicine, 1997
- A Relativistic Bremsstrahlung/Inverse Compton Origin for 2EG J1857+0118 Associated with Supernova Remnant W44The Astrophysical Journal, 1997
- In-orbit performance and calibration of the Rossi X-ray Timing Explorer (RXTE) Proportional Counter Array (PCA)Published by SPIE-Intl Soc Optical Eng ,1996
- A Circumstellar Shell Model for the Cassiopeia A Supernova RemnantThe Astrophysical Journal, 1996
- EGRET Observations of Radio-bright Supernova RemnantsThe Astrophysical Journal, 1996
- A Search for Ultra–High-Energy Gamma-Ray Emission from Five Supernova RemnantsThe Astrophysical Journal, 1995
- Electron acceleration in a nonlinear shock model with applications to supernova remnantsThe Astrophysical Journal, 1991
- EXOSAT observations of the Cassiopeia A supernova remnantThe Astrophysical Journal, 1988
- The X-ray structure and mass of the Cassiopeia A supernova remnantMonthly Notices of the Royal Astronomical Society, 1980
- Results of a Search for Optical PulsarsThe Astrophysical Journal, 1971