Discovery of a Color-selected Quasar at z = 5.50.

نویسندگان

  • Stern
  • Spinrad
  • Eisenhardt
  • Bunker
  • Dawson
  • Stanford
  • Elston
چکیده

We present observations of RD J030117+002025, a quasar at z=5.50 discovered from deep, multicolor, ground-based observations covering 74 arcmin2. This is the most distant quasar or active galaxy currently known. The object was targeted as an R-band dropout, with RAB>26.3 (3 sigma limit in a 3&arcsec; diameter region), IAB=23.8, and zAB=23.4. The Keck/Low-Resolution Imaging Spectrometer spectrum shows broad Lyalpha/N v lambda1240 emission and sharp absorption decrements from the highly redshifted hydrogen forests. The fractional continuum depression due to the Lyalpha forest is DA=0.90. RD J030117+002025 is the least luminous high-redshift quasar known (MB approximately -22.7).

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عنوان ژورنال:
  • The Astrophysical journal

دوره 533 2  شماره 

صفحات  -

تاریخ انتشار 2000