TY - JOUR SP - 480 VL - 646 IS - 1 N1 - Copyright © 2006. The American Astronomical Society. All rights reserved. UR - http://dx.doi.org/10.1086/504683 SN - 1538-4357 A1 - Farihi, J A1 - Hoard, DW A1 - Wachter, S JF - Astrophysical Journal AV - public Y1 - 2006/07/20/ EP - 492 TI - White dwarf-red dwarf systems resolved with the Hubble Space Telescope. I. First results N2 - First results are presented for a Hubble Space Telescope (HST) Advanced Camera for Surveys snapshot study of white dwarfs with likely red dwarf companions. Of 48 targets observed and analyzed so far, 27 are totally or partially resolved into two or more components, while an additional 15 systems are almost certainly unresolved binaries. These results provide the first direct empirical evidence for a bimodal distribution of orbital separations among binary systems containing at least one white dwarf. ID - discovery1477409 KW - binaries: general; stars: evolution; stars: formation; stars: fundamental parameters; stars: low-mass KW - brown dwarfs; stars: luminosity function KW - mass function; white dwarfs ER -