High Longevity Microlensing Events and Dark Matter Black Holes
نویسنده
چکیده
Gravitational microlensing has been employed to identify massive halo objects by their amplilification of distant sources; MACHO searches have studied event times 2h∼ t0 < ∼ 2y corresponding masses in the range 10M⊙ < ∼ M < ∼ 100M⊙. We suggest that larger masses up to 10M⊙ are also of considerable interest. It has not been excluded that there is a significant number of halo black holes with such masses as suggested by cosmological entropy considerations and potentially detectable by high longevity microlensing events.
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