Neutron Stars and Black Holes as MACHOs
نویسندگان
چکیده
We consider the contribution of neutron stars and black holes to the dynamical mass of galactic halos. In particular, we show that if these compact objects were produced by an early generation of stars with initial metallicity ∼< 10 Z⊙, they can contribute up to 30–40% of the Galactic halo mass without violating constraints from chemical evolution. This scenario is consistent with the recent results on halo microlensing, the presence of enriched hot gas in clusters and groups of galaxies, and other observations in the context of this model.
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