Narrow associated quasi-stellar object absorbers: clustering, outflows and the line-of-sight proximity effect
نویسندگان
چکیده
منابع مشابه
1WGA J2223.7-0206: a Narrow–Line Quasi–Stellar Object in the XMM-Newton field of view of 3C445⋆
We report the discovery of a Narrow Line QSO located at about 1.3 from the Broad Line Radio Galaxy 3C445. The source, 1WGA J2223.7-0206 , although already revealed by ROSAT, has never been optically identified previously. An XMM-Newton observation of 3C445 has allowed, for the first time, an accurate X-ray spectral study of 1WGA J2223.7-0206 , revealing an ultra-soft spectrum and fast flux vari...
متن کاملThe Line-of-sight Proximity Effect and the Mass of Quasar Host Halos
We show that the Lyman-α (Lyα) optical depth statistics in the proximity regions of quasar spectra depend sensitively on the mass of the dark matter halos hosting the quasars. This is owing to both the overdensity around the quasars and the associated infall of gas toward them. For a fiducial quasar host halo mass of 3.0± 1.6 h × 10 M⊙, as inferred by Croom et al. from clustering in the 2dF QSO...
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We report the discovery of the faint (V ≃ 21.7) quasar QSO 03027−0010 at z = 2.808 in the vicinity of Q 0302−003, one of the few quasars observed with STIS to study intergalactic He absorption. Together with another newly discovered QSO at z = 2.29, there are now 6 QSOs known near the line of sight towards Q 0302−003, of which 4 are located within the redshift region 2.76 < ∼ z < ∼ 3.28 cove...
متن کاملthe effect of explicit teaching of metacognitive vocabulary learning strategies on recall and retention of idioms
چکیده ندارد.
15 صفحه اولthe evaluation of language related engagment and task related engagment with the purpose of investigating the effect of metatalk and task typology
abstract while task-based instruction is considered as the most effective way to learn a language in the related literature, it is oversimplified on various grounds. different variables may affect how students are engaged with not only the language but also with the task itself. the present study was conducted to investigate language and task related engagement on the basis of the task typolog...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2008
ISSN: 0035-8711,1365-2966
DOI: 10.1111/j.1365-2966.2008.13375.x