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تسجيل مستخدم جديدEROS 2 proper motion survey: Constraints on the halo white dwarfs
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We are conducting a 377-square-degree proper motion survey in the ~V and I bands in order to determine the cool white dwarf contribution to the Galactic dark matter. Using the 250 square degrees for which we possess three epochs, and applying selection criteria designed to isolate halo-type objects, we find no candidates in a 5500 pc^3 effective volume for old, fast M_V=17 white dwarfs. We check the detection efficiency by cross-matching our catalogue with Luytens NLTT catalogue. The halo white dwarf contribution cannot exceed 5% (95% C.L.) for objects with M_V=17 and 1<V-I<1.5. The same conclusion applies to a 14Gyr halo composed of white dwarfs with hydrogen atmosphere, as modeled by Chabrier (99).
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