INTEGRAL, SNOBs, and baryonic dark matter

Abstract

view Abstract Citations (5) References (8) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS INTEGRAL, SNOBs, and Baryonic Dark Matter Gilmore, Gerard Abstract The gamma-ray surface brightness distribution is proportional to the surface mass distribution and to the flux density of cosmic rays. Given adequate gamma-ray data one can determine both these distributions. Local enhancements in the cosmic-ray intensity, visible as high surface brightness fluctuations which do not correspond to mass density enhancements, signal regions of enhanced cosmic-ray acceleration. Such regions are expected to occur in those places where multiple supernova remnants and many hot OB stars are found-- SNOBs. SNOBs probably dominate the energetics of the interstellar medium (ISM) as well as the cosmic-ray flux. They sometimes also blow through the thin disk ISM, creating 'chimneys' which feed high-excitation material into the Galactic halo. High spatial resolution gamma-ray imaging provides a unique means to study such phenomena. In places where the cosmic-ray flux is more uniformly extended, particularly at high Galactic latidudes, the gamma-ray surface brightness is a tracer of the surface mass density. One may use this to determine what fraction of the 'dark' massive Galactic halo is made of baryonic matter in a form which is capable of interacting with cosmic rays. Current data allow an upper limit of only 15% of the total mass of the Galactic dark halo to be baryonic matter which is not in compact objects. Publication: The Astrophysical Journal Supplement Series Pub Date: June 1994 DOI: 10.1086/192011 Bibcode: 1994ApJS...92..539G Keywords: Dark Matter; Galactic Cosmic Rays; Galactic Halos; Gamma Ray Astronomy; Gamma Rays; Hot Stars; Supernova Remnants; Baryons; Mass Distribution; Massive Stars; Milky Way Galaxy; Space Radiation; ISM: COSMIC RAYS; COSMOLOGY: DARK MATTER; GAMMA RAYS: THEORY full text sources ADS |