The Frequency of Intrinsic X-Ray Weakness among Broad Absorption Line Quasars
نویسندگان
چکیده
منابع مشابه
Weak Hard X-ray Emission from Broad Absorption Line Quasars: Evidence for Intrinsic X-ray Weakness
We report NuSTAR observations of a sample of six X-ray weak broad absorption line (BAL) quasars. These targets, at z = 0.148–1.223, are among the optically brightest and most luminous BAL quasars known at z< 1.3. However, their rest-frame ≈ 2 keV luminosities are 14 to > 330 times weaker than expected for typical quasars. Our results from a pilot NuSTAR study of two low-redshift BAL quasars, a ...
متن کاملThe X-ray Absorber in Broad Absorption Line Quasars
Recent observations of Broad Absorption Line (BAL) quasars demonstrated that the soft X-ray emission of these objects is extremely weak and convincing evidence for very strong absorption by a high column density (∼ 10 cm) was obtained for PG 1411+442, even though it is one of the few BAL QSOs strongly detected in soft X-rays. This paper examines the ionization status and geometry of the X-ray a...
متن کاملThe X-ray emission from broad absorption line quasars
Pointed ASCA observations as well as archival ROSAT data are used for a study of the X-ray emission of the three BAL Quasars LBQS 2212-1759, PG 1411+442, and PG 0043+039. All three objects are found to be X-ray quiet, possibly due to substantial intrinsic absorption with NH > 1023 cm−2 but might have intrinsically a more typical spectral energy distribution. This picture is supported by explici...
متن کاملWEAK HARD X-RAY EMISSION FROM TWO BROAD ABSORPTION LINE QUASARS OBSERVED WITH NuSTAR: COMPTON-THICK ABSORPTION OR INTRINSIC X-RAY WEAKNESS?
We present NuSTAR hard X-ray observations of two X-ray weak broad absorption line (BAL) quasars, PG 1004+130 (radio loud) and PG 1700+518 (radio quiet). Many BAL quasars appear X-ray weak, probably due to absorption by the shielding gas between the nucleus and the accretion-disk wind. The two targets are among the optically brightest BAL quasars, yet they are known to be significantly X-ray wea...
متن کاملOn the absorption of X-ray bright Broad Absorption Line Quasars
Context. Most X-ray studies of Broad Absorption Line Quasars (BALQSOs) found significant (NH ∼ 1022−24 cm−2) intrinsic column densities of gas absorbing an underlying typical power-law continuum emission, in agreement with expectations from radiatively driven accretion disk wind models. However, direct spectral analysis was performed only on a limited number of bright sources. Aims. We investig...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2018
ISSN: 1538-4357
DOI: 10.3847/1538-4357/aabe8d