Observations of the Large Magellanic Cloud in high-energy gamma rays

view Abstract Citations (107) References (22) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Observations of the Large Magellanic Cloud in High-Energy Gamma Rays Sreekumar, P. ; Bertsch, D. L. ; Dingus, B. L. ; Fichtel, C. E. ; Hartman, R. C. ; Hunter, S. D. ; Kanbach, G. ; Kniffen, D. A. ; Lin, Y. C. ; Mattox, J. R. ; Mayer-Hasselwander, H. A. ; Michelson, P. F. ; von Montigny, C. ; Nolan, P. L. ; Pinkau, K. ; Schneid, E. J. ; Thompson, D. J. Abstract The Large Magellanic Cloud (LMC) provides a valuable site to study gamma-ray production, intensity, and distribution in an external galaxy. Using 4 weeks of data from the Energetic Gamma Ray Experiment Telescope (EGRET) aboard the Compton Gamma Ray Observatory, high-energy gamma-ray emission was detected for the first time from the LMC region. These gamma rays are believed to be produced primarily through the interaction of cosmic rays with interstellar matter. Hence, combined with a knowledge of the interstellar matter distribution, they can provide a direct measure of the cosmic-ray density in an external galaxy. The results obtained from EGRET observations indicate that the level of cosmic rays in the LMC is comparable to that in our Galaxy. The integrated flux above 100 MeV is (1.9 +/- 0.4) x 10^-7^ photons (cm^2^ s)^-1^. The measured flux suggests a cosmic-ray density level consistent with that expected from a quasi- stable equilibrium model. This is the first detection of a normal galaxy outside the Milky Way in high-energy gamma rays. Publication: The Astrophysical Journal Pub Date: December 1992 DOI: 10.1086/186651 Bibcode: 1992ApJ...400L..67S Keywords: Cosmic Rays; Gamma Ray Astronomy; Gamma Rays; Magellanic Clouds; Gamma Ray Observatory; Interstellar Matter; Spatial Distribution; Space Radiation; GALAXIES: MAGELLANIC CLOUDS; GAMMA RAYS: OBSERVATIONS; ISM: COSMIC RAYS full text sources ADS | data products SIMBAD (2) NED (1) HEASARC (1)