ar X iv : a st ro - p h / 00 11 50 6 v 1 2 8 N ov 2 00 0 MACHO Project Limits on Black Hole Dark Matter in the 1 - 30 Solar Mass Range
نویسنده
چکیده
We report on a search for long duration microlensing events towards the Large Magellanic Cloud. We find none, and therefore put limits on the contribution of high mass objects to the Galactic dark matter. At 95% confidence level we exclude objects in the mass range 0.3M⊙ to 30.0M⊙ from contributing more than 4 × 10 M⊙ to the Galactic halo. Combined with earlier results, this means that objects with masses under 30M⊙ cannot make up the entire dark matter halo if the halo is of typical size. For a typical dark halo, objects with masses under 10M⊙ contribute less than 40% of the dark matter. Subject headings: dark matter — Galaxy: structure, halo — gravitational lensing — Stars: high mass — black holes
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