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Discovery of Radio-loud Quasars with Redshifts above 4 from the PMN sample

I. M. Hook·R. G. McMahon·P. A. Shaver·I. A. G. Snellen
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Abstract

We present results of a new, large survey for high-redshift radio-loud quasars, which targets quasars with z>4. The survey is based on the PMN and NVSS radio surveys, optically identified using digitised UKST B, R and I plates. Six new z>4 flat-spectrum QSOs have been discovered, and one previously known z>4 QSO rediscovered, based on their red optical colours. The QSOs discovered in this survey are bright in both radio and optical bands; in particular PMN J1451-1512 (z=4.763, I=17.3, R=19.1) and PMN J0324-2918 (z=4.630, R=18.7) are very luminous. PMN J1451-1512 at z=4.763 is also now the most distant radio-selected quasar. In addition, 9 new quasars with 3.5 4 QSOs with S>= 72mJy and R< 21mag.

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I. M. Hook, R. G. McMahon, P. A. Shaver, I. A. G. Snellen. 2002-07-03. Discovery of Radio-loud Quasars with Redshifts above 4 from the PMN sample. https://doi.org/10.1051/0004-6361%3A20020869

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