A population of high-redshift type 2 quasars - I. Selection criteria and optical spectra
نویسندگان
چکیده
منابع مشابه
High - redshift obscured quasars
Using mid-infrared and radio criteria, we select a sample of candidate z ∼ 2 obscured quasars. Optical spectroscopy confirms about half of these as type-2 quasars, and modelling the population suggests 50-80% of the quasars are obscured. We find some flat radio spectrum type-2 quasars, and tentative evidence for obscuration unrelated to the torus. Using a similar sample, we also find evidence f...
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Measurements ~t 1.2, 1.~, and 2.2 μm have been combined with visual spectrophotometry o~ 21 quasai:s havmg. redshifts z ;:;: 2.66. T~e primary result of this study is that the rest frame vism~.l/ultravIC?let contmua of the high-redshift quasars are well described by a sum of a power-law contmuum with slope -.-0.~ ~nd a 3000 A bump. The rest frame visual/ultraviolet continua of these quasars are...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2006
ISSN: 0035-8711
DOI: 10.1111/j.1365-2966.2006.10563.x