Hubble Deep Field Constraint on Baryonic Dark Matter
نویسندگان
چکیده
We use a new technique to search for faint red stars in the Hubble Deep Field (HDF) imaged by the Wide Field Camera (WFC2) on the Hubble Space Telescope. We construct a densely sampled stellar light profile from a set of undersampled images of bright stars in a low-latitude field. Comparison of this stellar light profile to densely sampled profiles of individual objects in the HDF constructed from multiple undersampled dithers allows us to distinguish unambiguously between stars and galaxies to I = 26.3. We find no stars with V − I > 1.8 in the outer 90% of the volume probed. This result places strong and general constraints on the I band luminosity of the constituents of the Galactic dark halo: MI > 15.9 + 5 3 log (
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