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Boson Stars: Alternatives to primordial black holes?

Eckehard W. Mielke·Franz E. Schunck
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Abstract

The present surge for the astrophysical relevance of boson stars stems from the speculative possibility that these compact objects could provide a considerable fraction of the non-baryonic part of dark matter within the halo of galaxies. For a very light `universal' axion of effective string models, their total gravitational mass will be in the most likely range of \sim 0.5 M_\odot of MACHOs. According to this framework, gravitational microlensing is indirectly ``weighing" the axion mass, resulting in \sim 10^{-10} eV/c^2. This conclusion is not changing much, if we use a dilaton type self-interaction for the bosons. Moreover, we review their formation, rotation and stability as likely candidates of astrophysical importance.

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Eckehard W. Mielke, Franz E. Schunck. 2000-01-20. Boson Stars: Alternatives to primordial black holes?. https://doi.org/10.1016/s0550-3213(99)00492-7

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