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Title: X-ray follow-up observations of unidentified VHE {gamma}-ray sources

Abstract

A large fraction of the recently discovered Galactic Very High Energy (VHE) source population remains unidentified to date. VHE {gamma}-ray emission traces high energy particles in these sources, but for example in case of hadronic processes also the gas density at the emission site. Moreover, the particles have sufficiently long lifetimes to be able to escape from their acceleration sites. Therefore, the {gamma}-ray sources or at least the areas of maximum surface brightness are in many cases spatially offset from the actual accelerators. A promising way to identify the objects in which the particles are accelerated seems to be to search for emission signatures of the acceleration process (like emission from shock-heated plasma). Also the particles themselves (through primary or secondary synchrotron emission) can be traced in lower wavebands. Those signatures are best visible in the X-ray band, and current X-ray observatories are well suited to conduct such follow-up observations. Some aspects of the current status of these investigations are reviewed.

Authors:
Publication Date:
OSTI Identifier:
21255150
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1085; Journal Issue: 1; Conference: 4. international meeting on high energy gamma-ray astronomy, Heidelberg (Germany), 7-11 Jul 2008; Other Information: DOI: 10.1063/1.3076636; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; ACCELERATION; BRIGHTNESS; COSMIC GAMMA SOURCES; GALAXY NUCLEI; GAMMA RADIATION; HADRONS; LIFETIME; PHOTON EMISSION; PLASMA; SYNCHROTRONS; TELESCOPES; X RADIATION

Citation Formats

Puehlhofer, Gerd. X-ray follow-up observations of unidentified VHE {gamma}-ray sources. United States: N. p., 2008. Web. doi:10.1063/1.3076636.
Puehlhofer, Gerd. X-ray follow-up observations of unidentified VHE {gamma}-ray sources. United States. doi:10.1063/1.3076636.
Puehlhofer, Gerd. Wed . "X-ray follow-up observations of unidentified VHE {gamma}-ray sources". United States. doi:10.1063/1.3076636.
@article{osti_21255150,
title = {X-ray follow-up observations of unidentified VHE {gamma}-ray sources},
author = {Puehlhofer, Gerd},
abstractNote = {A large fraction of the recently discovered Galactic Very High Energy (VHE) source population remains unidentified to date. VHE {gamma}-ray emission traces high energy particles in these sources, but for example in case of hadronic processes also the gas density at the emission site. Moreover, the particles have sufficiently long lifetimes to be able to escape from their acceleration sites. Therefore, the {gamma}-ray sources or at least the areas of maximum surface brightness are in many cases spatially offset from the actual accelerators. A promising way to identify the objects in which the particles are accelerated seems to be to search for emission signatures of the acceleration process (like emission from shock-heated plasma). Also the particles themselves (through primary or secondary synchrotron emission) can be traced in lower wavebands. Those signatures are best visible in the X-ray band, and current X-ray observatories are well suited to conduct such follow-up observations. Some aspects of the current status of these investigations are reviewed.},
doi = {10.1063/1.3076636},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1085,
place = {United States},
year = {Wed Dec 24 00:00:00 EST 2008},
month = {Wed Dec 24 00:00:00 EST 2008}
}
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