The Reddest Quasars

  • Michael Gregg (U.C. Davis)
  • Mark Lacy (SIRTF)
  • Robert Becker (U.C. Davis)
  • Richard White (STScI)
  • David Helfand (Columbia)
  • Eilat Glikman (Columbia)

  • There is much evidence that quasars begin life enshrouded in a dusty cocoon, where they lie hidden from optical surveys. In collaboration with M. Lacy (SIRTF), R. Becker (UCD), D. Helfand (Columbia), and R. White, (STScI), I am using the 2 Micron All-Sky Survey (2MASS) in conjunction with the FIRST Survey and optical catalogs to select optically faint, infrared bright quasar candidates for optical and infrared spectroscopy and imaging follow-up at Keck and the NASA InfraRed Telescope Facility (IRTF). We have now discovered several dozen extremely red, probably very dusty, quasars at redshifts 0.5 to 2.6. Assessing the population of these objects is critical for understanding the general quasar phenomenon because their numbers relative to the standard blue quasars constrain the lifetime of the dusty phase. Click here to see color-magnitude comparisons of the K-band selected red quasars with normal FIRST survey quasars selected in the optical.

    The broad emission line nature of these objects is discovered using IRTF SpeX and Keck ESI spectroscopy of these objects.

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    UCD Physics Dept.
    Cosmology Research Group
    Institute of Geophysics and Planetary Physics at the Lawrence Livermore National Laboratory

    Modified February, 2003
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