Could MACHOS be Primordial Black Holes formed during the QCD Epoch?
نویسنده
چکیده
Observations by the MACHO collaboration indicate that a signi cant fraction of the galactic halo dark matter may be in form of compact objects with masses M 0:5M . Identi cation of these objects as red or white dwarfs is problematic due to stringent observational upper limits on such dwarf populations. Primordial black hole (PBH) formation from pre-existing density uctuations is facilitated during the cosmic QCD transition due to a signi cant decrease in pressure forces. For generic initial density perturbation spectra this implies that essentially all PBHs may form with masses close to the QCD-horizon scale, M QCD
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تاریخ انتشار 1998