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arXiv · astro-ph/9901058

Gravitational microlensing and dark matter in the galactic halo

Ph. Jetzer
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Abstract

We present the basics of microlensing and give an overview of the results obtained so far. We also describe a scenario in which dark clusters of MACHOs (Massive Astrophysical Compact Halo Objects) and cold molecular clouds (mainly of $H_2$) naturally form in the halo at galactocentric distances larger than 10-20 kpc. Moreover, we discuss various experimental tests of this picture in particular a $γ$-ray emission from the clouds due to the scattering of high-energy cosmic-ray protons. Our estimate for the $γ$-ray flux turns out to be in remarkably good agreement with the recent discovery by Dixon et al. of a possible $γ$-ray emission from the halo using EGRET data.

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Ph. Jetzer. 1999-01-08. Gravitational microlensing and dark matter in the galactic halo. https://doi.org/10.1063/1.59348

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