ISO continuum observations of quasars at ${z=1{-}4}$
نویسندگان
چکیده
منابع مشابه
ISO continuum observations of quasars at z = 1 - 4 ⋆ I . Spectral energy distributions of quasars from the UV to far - infrared
Eight luminous quasars with −30 < MB < −27 at z = 1.4 3.7 have been observed in the midand far-infrared using ISO. All the quasars have been detected in the mid-infrared bands of ISOCAM, while no far-infrared detections have been made with ISOPHOT. SEDs (Spectral Energy Distributions) from the UV to far-infrared have been obtained while supplementing ISO observations with photometry in the opti...
متن کاملOne Millimeter Continuum Observations of High Redshift Quasars
Upper limits to the one-millimeter continuum flux densities of the high redshift quasars 82 1225 + 31, Ton 490, and PHL 957 are presented. The upper limit to the power observed from these quasars at I mm is, on average, ! the observed power in the continuum at La. These observations are used to constrain the temperature of a hypoth'etical dust shell which reddens the quasar line and continuum e...
متن کاملEstimating the continuum of quasars using the articial neural networks
A lot of absorption lines are in the bluewards of Lyα emission line of quasar which is well-known as Lyαforest. Most of absorption lines in this forest belong to the Lyα absorption of the neutral hydrogen in the inter-galactic medium (IGM). For high redshift quasars and in the continuum with low and medium resolution, there are no many regions without absorption, so that, the quasar continuum i...
متن کاملThe Ionizing Continuum of Quasars
The ionizing continuum shape of quasars is generally not directly observable, but indirect arguments, based on photoionization models and thin accretion disk models suggest that it should peak in the extreme UV, and drop steeply into the soft X-ray regime. However, recent observations of very soft X-ray emission in low z quasars, and far UV emission of high z quasars, suggest that the ionizing ...
متن کاملVlba Observations of Z > 4 Radio-loud Quasars
We present high resolution (≤ 20 mas) observations of the radio continuum emission at 1.4 GHz from three high-redshift quasars: J1053−0016 (z = 4.29), 1235−0003 (z = 4.69), and J0913+5919 (z = 5.11), thereby doubling the number of z > 4 radio-loud quasars that have been imaged at mas resolution. The observations were carried out with the Very Long Baseline Array (VLBA) of the NRAO. All three so...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2001
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20000508