Astronomy and Astrophysics – Astronomy
Scientific paper
Jan 2011
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011aas...21733002v&link_type=abstract
American Astronomical Society, AAS Meeting #217, #330.02; Bulletin of the American Astronomical Society, Vol. 43, 2011
Astronomy and Astrophysics
Astronomy
Scientific paper
A major aim of VHE astronomy is the study of relativistic particle populations in the Galaxy and elsewhere, called here the Nonthermal Universe. The physics is often described in terms of cosmic rays, even though this is a notion that emphasizes the diffuse aspect. It had been predicted that with sufficiently large imaging atmospheric Cherenkov telescopes it should be possible to study also the particle sources. And indeed, various source classes have been found. In particular individual Galactic Supernova Remnants have been for the first time localized as particle sources at multi-TeV energies by the H.E.S.S. experiment. Two examples, SNR RX J1713.7-3946 and SN 1006, will be described together with their theoretical explanation in terms of the diffusive shock acceleration process. There is an interesting complementarity to X-ray astromomy and radio continuum astronomy which also rely on mechanical energy production, and from similar sources. On a galactic scale nonthermal particle production can best be studied for starburst galaxies whose strong activity makes them detectable in VHE gamma-rays, allowing us to assess the differences between particle propagation in our Galaxy and in such energetic objects, beyond suggesting strongly that the sources are the same. Indeed, in 2009, the nearby starburst galaxies NGC 253 and M 82 have been discovered in the Northern and Southern Hemispheres by the H.E.S.S. and VERITAS telescope systems, respectively, as well as at lower gamma-ray energies by the Fermi LAT telescope in space; some of the key results will be discussed. Since galaxy-galaxy mergers in galaxy clusters should lead to similar processes that should generate a strong nonthermal component there together with mass accretion, it is to be hoped that future, larger instruments will be able to turn present low upper limits into detections.
No associations
LandOfFree
H.E.S.S. and Cosmic Rays does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with H.E.S.S. and Cosmic Rays, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and H.E.S.S. and Cosmic Rays will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1401607