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Discovery of a Color-Selected Quasar at z=5.50

Daniel Stern·Hyron Spinrad·Peter Eisenhardt·Andrew J. Bunker·Steve Dawson·S. A. Stanford·Richard Elston
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Abstract

We present observations of RD J030117+002025, a quasar at z=5.50 discovered from deep, multi-color, ground-based observations covering 74 square arcmin. This is the most distant quasar or AGN currently known. The object was targeted as an R-band dropout, with R(AB)>26.3 (3-sigma limit in a 3 arcsec diameter region), I(AB)=23.8, and z(AB)=23.4. The Keck/LRIS spectrum shows broad Lyman-alpha/NV emission and sharp absorption decrements from the highly-redshifted hydrogen forests. The fractional continuum depression due to the Lyman-alpha forest is D(A)=0.90. RD J030117+002025 is the least luminous, high-redshift quasar known (M(B)~-22.7).

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Daniel Stern, Hyron Spinrad, Peter Eisenhardt, Andrew J. Bunker, Steve Dawson, S. A. Stanford, Richard Elston. 2000-02-17. Discovery of a Color-Selected Quasar at z=5.50. https://doi.org/10.1086/312614

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