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Related papers: Weak Hard X-ray Emission from Two Broad Absorption…

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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…

We investigate the X-ray properties of PG 1004+130, a low-redshift radio-loud broad absorption line (BAL) quasar with a hybrid FR I/FR II radio morphology. The 22.2 ks XMM-Newton and 41.6 ks Chandra observations presented here are the first…

We present NuSTAR hard X-ray (3-79 keV) observations of three Type 2 quasars at z ~ 0.4-0.5, optically selected from the Sloan Digital Sky Survey (SDSS). Although the quasars show evidence for being heavily obscured Compton-thick systems on…

We utilize recent NuSTAR observations (co-added depth $\approx55$-120 ks) of PG $1001+054$, PG $1254+047$, and PHL 1811 to constrain their hard X-ray ($\gtrsim5$ keV) weakness and spectral shapes, and thus to investigate the nature of their…

High Energy Astrophysical Phenomena · Physics 2022-09-14 Chaojun Wang , B. Luo , W. N. Brandt , D. M. Alexander , F. E. Bauer , S. C. Gallagher , Jian Huang , Hezhen Liu , D. Stern

We present the results of recent Chandra, XMM-Newton, and Hubble Space Telescope observations of the radio-loud (RL), broad absorption line (BAL) quasar PG 1004+130. We compare our new observations to archival X-ray and UV data, creating…

High Energy Astrophysical Phenomena · Physics 2015-05-07 A. E. Scott , W. N. Brandt , B. P. Miller , B. Luo , S. C. Gallagher

We present combined $\approx 14-37~\rm ks$ Chandra observations of seven $z = 1.6-2.7$ broad absorption line (BAL) quasars selected from the Large Bright Quasar Survey (LBQS). These seven objects are high-ionization BAL (HiBAL) quasars, and…

High Energy Astrophysical Phenomena · Physics 2018-06-13 Hezhen Liu , B. Luo , W. N. Brandt , S. C. Gallagher , G. P. Garmire

We present 4-7 ks Chandra observations of 35 Broad Absorption Line (BAL) quasars from the Large Bright Quasar Survey, the largest sample of sensitive, 0.5-8.0 keV X-ray observations of this class of quasars to date. The limited ranges in…

Astrophysics · Physics 2009-11-11 S. C. Gallagher , W. N. Brandt , G. Chartas , R. Priddey , G. P. Garmire , R. M. Sambruna

We analyze the long-term (rest-frame 3-30 yr) X-Ray variability of eleven broad absorption line (BAL) quasars, mainly to constrain the variation properties of the X-Ray absorbing shielding gas that is thought to play a critical role in BAL…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Cristian Saez , William N. Brandt , Sarah C. Gallagher , Franz E. Bauer , Gordon P. Garmire

The intrinsic column density (NH) distribution of quasars is poorly known. At the high obscuration end of the quasar population and for redshifts z<1, the X-ray spectra can only be reliably characterized using broad-band measurements which…

We report on an observation of the Broad Absorption Line (BAL) quasar PG 1115+080 performed with the XMM-Newton observatory. Spectral analysis reveals the second case of a relativistic X-ray absorbing outflow in a BAL quasar. The first case…

Astrophysics · Physics 2009-11-07 G. Chartas , W. N. Brandt , S. C. Gallagher

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 (~ 10^23.5 cm^-2) was…

Astrophysics · Physics 2009-10-31 T. G. Wang , W. Brinkmann , W. Yuan , J. X. Wang , Y. Y. Zhou

We present new results on X-ray properties of radio loud broad absorption line (BAL) quasars and focus on broad-band spectral properties of a high ionization BAL (HiBAL) compact steep spectrum (CSS) radio-loud quasar 1045+352. This HiBAL…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 M. Kunert-Bajraszewska , A. Siemiginowska , K. Katarzynski , A. Janiuk

We report X-ray observations of the most distant known gravitationally lensed quasar, J0439+1634 at $z=6.52$, which is also a broad absorption line (BAL) quasar, using the XMM-Newton Observatory. With a 130 ks exposure, the quasar is…

The X-ray weakness of broad absorption line (BAL) quasars in comparison to non-BAL objects is possibly caused by the absorption of X-ray emission by the shielding material near the equatorial plane. On the other hand, the radio-loud BALQSOs…

Astrophysics of Galaxies · Physics 2015-06-23 M. Kunert-Bajraszewska , K. Katarzynski , A. Janiuk

We report on the results of XMM-Newton observations of two Broad Absorption Line Quasars (BAL QSOs), Q1246-057 and SBS 1542+541. Unprecedented sensitivity of XMM allows spectral analysis of these X-ray weak sources. The X-ray spectral data…

Astrophysics · Physics 2009-11-07 D. Grupe , S. Mathur , M. Elvis

We report NuSTAR observations of NuSTAR J033202-2746.8, a heavily obscured, radio-loud quasar detected in the Extended Chandra Deep Field-South, the deepest layer of the NuSTAR extragalactic survey (~400 ks, at its deepest). NuSTAR…

We have selected a sample of broad absorption line (BAL) quasars which show significant radio variations, indicating the presence of polar BAL outflows. We obtained snapshot XMM observations of four polar BAL QSOs, to check whether strong…

Astrophysics · Physics 2009-11-13 Junxian Wang , Peng Jiang , Hongyan Zhou , Tinggui Wang , Xiaobo Dong , Huiyuan Wang

We present results from multi-epoch spectral analysis of XMM-Newton and Chandra observations of the mini broad absorption line (BAL) quasar PG 1115+080. This is one of the few X-ray detected mini-BAL quasars to date that is bright enough in…

Astrophysics · Physics 2008-11-26 G. Chartas , W. N. Brandt , S. C. Gallagher , D. Proga

We report on the first ten identifications of sources serendipitously detected by the NuSTAR to provide the first sensitive census of the cosmic X-ray background (CXB) source population at >10 keV. We find that these NuSTAR-detected sources…

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