Spectroscopy of spatially extended material around high-redshift radio-loud quasars
نویسندگان
چکیده
منابع مشابه
High-Redshift, Radio-Loud Quasars
I discuss two programs to study radio-loud quasars at high (z ∼ > 4) redshift. Quasars are the most luminous, non-transient objects known and are observed to the earliest cosmic epochs. At lower redshifts, radio-loud quasars are associated with host galaxies having de Vaucoleurs profiles. By association, identifying and studying a sample of high-redshift, radio-loud quasars provides important c...
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We present near-infrared spectra of seven radio-loud quasars with a median red-shift of 2.1, five of which were previously known to have Lyα nebulae. Extended [OIII]λ5007 and Hα emission are evident around six objects, at the level of a few times 10 −16 erg cm −2 arcsec −2 s −1 within ≃ 2 arcsec of the nucleus (≡ 16 kpc in the adopted cosmology). Nuclear [OII]λ3727 is detected in three of the 5...
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We present results from two surveys for radio-loud quasars. These are (1) a northern survey reaching S 5GHz = 0:2Jy and (2) the Parkes QSO survey reaching S 2:7GHz = 0:25Jy which together cover most of the sky. Both surveys use digitised plate material to identify the majority of the radio sources and CCD images to identify the optically fainter sources. The northern survey was targeted speciic...
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We present the results of X-ray spectroscopic observations with XMM-Newton for four high-redshift radio-loud quasars at z > 4. Among these, three objects, namely, GBB1508+5714, PMNJ0324-2918, and PKSB1251-407 do not show soft X-ray spectral flattening; the derived upper limits on assumed intrinsic absorption are (3.3 − 17.3) × 10 cm, the least of which is among the most stringent limits for z >...
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We present optical spectroscopic data for a complete sample of 161 S5GHz ≥ 0.2Jy, flatspectrum radio sources. The sources were observed as part of a survey for high redshift, radio-loud quasars, and were selected for spectroscopic follow-up based on criteria of red optical colour and unresolved optical counterpart, as measured from APM scans of POSS-I plates. 13 objects from the spectroscopic s...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 1991
ISSN: 0004-637X,1538-4357
DOI: 10.1086/170660