Gamma ray astronomy and baryonic dark matter

Abstract

Recently, Dixon et al. have re-analyzed the EGRET data, finding a statistically significant diffuse $\gamma$-ray emission from the galactic halo. We show that this emission can naturally be explained within a previously-proposed model for baryonic dark matter, in which $\gamma$-rays are produced through the interaction of high-energy cosmic-ray protons with cold $H_2$ clouds clumped into dark clusters - these dark clusters supposedly populate the outer galactic halo and can show up in microlensing observations. Our estimate for the halo $\gamma$-ray flux turns out to be in remarkably good agreement with the discovery by Dixon et al. We also address future prospects to test our predictions.

9 pages, 1 figure included, to appear in ApJ 510, L103 (1999)

References in corpus (7)

• EGRET Observations of the Extragalactic Gamma Ray Emission
• Extreme scattering events and Galactic dark matter
• Evidence for a Galactic gamma ray halo
• Lensing of Stars by Spherical Gas Clouds
• Halo dark clusters of brown dwarfs and molecular clouds
• Microlensing Halo Models with Abundant Brown Dwarfs
• Binary brown dwarfs in the galactic halo?

Cited by in corpus (13)

• Evidence of Fermi bubbles around M31
• Thermal stability of cold clouds in galaxy halos
• On the Interaction Between Cosmic Rays and Dark Matter Molecular Clouds in the Milky Way. l Basic Considerations
• Possible detection of the M31 rotation in WMAP data
• Supersymmetric dark matter in M31: can one see neutralino annihilation with CELESTE?
• Molecular hydrogen as baryonic dark matter
• Dense gas clouds and the Unidentified EGRET sources
• CMB as a possible new tool to study the dark baryons in galaxies
• The rotational kinetic Sunyaev-Zeldovich contribution to the temperature asymmetry toward the M31 halo
• Virial clouds explaining the observed rotational asymmetry in the galactic halos
• On the Galactic Halos Rotation by Planck Data
• Microlensing by gas filaments
• Anomaly distribution in quasar magnitudes: a test of lensing by an hypothetic Supergiant Molecular Cloud in the Galactic halo