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MACHOs as brown dwarfs

F. De Paolis·G. Ingrosso·Ph. Jetzer·M. Roncadelli
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Abstract

Recent observations of microlensing events in the Large Magellanic Cloud suggest that a sizable fraction of the galactic halo is in the form of Massive Astrophysical Compact Halo Objects (MACHOs). Although the average MACHO mass is presently poorly known, the value $\sim 0.1 M_{\odot}$ looks as a realistic estimate, thereby implying that brown dwarfs are a viable and natural candidate for MACHOs. We describe a scenario in which dark clusters of MACHOs 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.

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F. De Paolis, G. Ingrosso, Ph. Jetzer, M. Roncadelli. 1998-03-17. MACHOs as brown dwarfs. https://arxiv.org/abs/astro-ph/9803200

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