Sign on

SAO/NASA ADS Astronomy Abstract Service

· Find Similar Abstracts (with default settings below)
· Electronic Refereed Journal Article (HTML)
· Full Refereed Journal Article (PDF/Postscript)
· arXiv e-print (arXiv:astro-ph/9702056)
· On-line Data
· References in the article
· Citations to the Article (70) (Citation History)
· Refereed Citations to the Article
· SIMBAD Objects (7)
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
A Possible Site of Cosmic Ray Acceleration in the Supernova Remnant IC 443
Authors:
Keohane, Jonathan W.; Petre, R.; Gotthelf, Eric V.; Ozaki, M.; Koyama, K.
Publication:
Astrophysical Journal v.484, p.350 (ApJ Homepage)
Publication Date:
07/1997
Origin:
APJ
ApJ Keywords:
ACCELERATION OF PARTICLES, RADIATION MECHANISMS: NONTHERMAL, SHOCK WAVES, ISM: COSMIC RAYS, ISM: SUPERNOVA REMNANTS, ISM: INDIVIDUAL ALPHANUMERIC: IC 443
DOI:
10.1086/304329
Bibliographic Code:
1997ApJ...484..350K

Abstract

We present evidence for shock acceleration of cosmic rays to high energies (~10 TeV) in the supernova remnant IC 443. X-ray imaging spectroscopy with ASCA reveals two regions of particularly hard emission: an unresolved source embedded in an extended emission region, and a ridge of emission coincident with the southeastern rim. Both features are located on part of the radio shell where the shock wave is interacting with molecular gas, and together they account for a majority of the emission at 7 keV. Though we would not have noticed it a priori, the unresolved feature is coincident with one resolved by the ROSAT HRI. Because this feature overlaps a unique region of flat radio spectral index ( alpha < 0.24), has about equal light-crossing and synchrotron loss times, and a power-law spectrum with a spectral index of alpha = 1.3 +/- 0.2, we conclude that the hard X-ray feature is synchrotron radiation from a site of enhanced particle acceleration. Evidence against a plerion includes a lack of observed periodicity (the pulsed fraction upper limit is 33%), the spectral similarity with the more extended hard region, the location of the source outside the 95% error circle of the nearby EGRET source, the fact that it is nestled in a bend in the molecular cloud ring with which IC 443 is interacting, and the requirement of an extremely high transverse velocity (>=5000 km s-1). We conclude that the anomalous feature is most likely tracing enhanced particle acceleration by shocks that are formed as the supernova blast wave impacts the ring of molecular clouds.
Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)
   

Find Similar Abstracts:

Use: Authors
Title
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints