Infrared/optical Energy Distributions of High-redshift Quasars
نویسندگان
چکیده
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 qmte similar to that of 3C 273, the archetype of low-redshift quasars. There do not appear to be any significant visual/ultraviolet properties distinguishing high-redshift quasars selected via visual or radio techniques. Subject headings: quasars spectrophotometry
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تاریخ انتشار 2009