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Title: Attenuation of VHE Gamma Rays by the Milky Way Interstellar Radiation Field

Abstract

The attenuation of very high energy gamma rays by pair production on the Galactic interstellar radiation field has long been thought of as negligible. However, a new calculation of the interstellar radiation field consistent with multi-wavelength observations by DIRBE and FIRAS indicates that the energy density of the Galactic interstellar radiation field is higher, particularly in the Galactic center, than previously thought. We have made a calculation of the attenuation of very high energy gamma rays in the Galaxy using this new interstellar radiation field which takes into account its nonuniform spatial and angular distributions. We find that the maximum attenuation occurs around 100 TeV at the level of about 25% for sources located at the Galactic center, and is important for both Galactic and extragalactic sources.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
881539
Report Number(s):
SLAC-PUB-11742
Journal ID: ISSN 0004-637X; ASJOAB; astro-ph/0511149; TRN: US0603163
DOE Contract Number:
AC02-76SF00515
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 640
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANGULAR DISTRIBUTION; ATTENUATION; ENERGY DENSITY; MILKY WAY; PAIR PRODUCTION; RADIATIONS; Astrophysics,ASTRO, HEPPH

Citation Formats

Moskalenko, Igor V., /Stanford U., HEPL, Porter, Troy A., /Louisiana State U., Strong, Andrew W., and /Garching, Max Planck Inst., MPE. Attenuation of VHE Gamma Rays by the Milky Way Interstellar Radiation Field. United States: N. p., 2006. Web. doi:10.1086/503524.
Moskalenko, Igor V., /Stanford U., HEPL, Porter, Troy A., /Louisiana State U., Strong, Andrew W., & /Garching, Max Planck Inst., MPE. Attenuation of VHE Gamma Rays by the Milky Way Interstellar Radiation Field. United States. doi:10.1086/503524.
Moskalenko, Igor V., /Stanford U., HEPL, Porter, Troy A., /Louisiana State U., Strong, Andrew W., and /Garching, Max Planck Inst., MPE. Wed . "Attenuation of VHE Gamma Rays by the Milky Way Interstellar Radiation Field". United States. doi:10.1086/503524. https://www.osti.gov/servlets/purl/881539.
@article{osti_881539,
title = {Attenuation of VHE Gamma Rays by the Milky Way Interstellar Radiation Field},
author = {Moskalenko, Igor V. and /Stanford U., HEPL and Porter, Troy A. and /Louisiana State U. and Strong, Andrew W. and /Garching, Max Planck Inst., MPE},
abstractNote = {The attenuation of very high energy gamma rays by pair production on the Galactic interstellar radiation field has long been thought of as negligible. However, a new calculation of the interstellar radiation field consistent with multi-wavelength observations by DIRBE and FIRAS indicates that the energy density of the Galactic interstellar radiation field is higher, particularly in the Galactic center, than previously thought. We have made a calculation of the attenuation of very high energy gamma rays in the Galaxy using this new interstellar radiation field which takes into account its nonuniform spatial and angular distributions. We find that the maximum attenuation occurs around 100 TeV at the level of about 25% for sources located at the Galactic center, and is important for both Galactic and extragalactic sources.},
doi = {10.1086/503524},
journal = {Astrophysical Journal},
number = ,
volume = 640,
place = {United States},
year = {Wed Apr 19 00:00:00 EDT 2006},
month = {Wed Apr 19 00:00:00 EDT 2006}
}
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