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We study the X-ray and optical properties of 16 Broad Absorption Line (BAL) quasars detected in about 3 degree square region common to the wide synoptic (W-1) component of the Canada-France-HawaiiTelescope Legacy Survey (CFHTLS) and the XMM…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 C. S. Stalin , R. Srianand , P. Petitjean

We present preliminary results from an investigation into broad absorption line (BAL) variability within a sample of 41 radio-loud quasars (RLQs). Using 28 new Hobby-Eberly Telescope (HET) spectra along with earlier Sloan Digital Sky Survey…

High Energy Astrophysical Phenomena · Physics 2012-01-13 B. P. Miller , C. A. Welling , W. N. Brandt , R. R. Gibson

We study a sample of six X-ray selected broad absorption line (BAL) quasi-stellar objects (QSOs) from the XMM-Newton Wide Angle Survey. All six objects are classified as BALQSOs using the classic balnicity index, and together they form the…

Broad absorption line (BAL) quasars are characterized by gas clouds that absorb flux at the wavelength of common quasar spectral features, although blueshifted by velocities that can exceed 0.1c. BAL features are interesting as signatures…

We compile a large sample of broad absorption lines (BAL) quasars with X-ray observations from the \xmm archive data and Sloan Digital Sky Survey Data Release 5. The sample consists of 41 BAL QSOs. Among 26 BAL quasars detected in X-ray,…

Astrophysics · Physics 2008-12-18 LuLu Fan , HuiYuan Wang , Tinggui Wang , Junxian Wang , Xiaobo Dong , Kai Zhang , Fuzhen Cheng

Broad absorption line quasars (commonly termed BALQSOs) contain the most dramatic examples of AGN-driven winds. The high absorbing columns in these winds, ~10^24 cm^-2, ensure that BALQSOs are generally X-ray faint. This high X-ray…

We present BeppoSAX observations of the Southern S1 region in the European Large Area ISO Survey (ELAIS). These observations cover an area of ~1.7 sq. deg. and reach an on-axis (~0.7 sq. deg) 2-10 keV (HX) sensitivity of ~10E-13 cgs. This…

This work presents the results of a Chandra study of 21 broad absorption line (BAL) radio-loud quasars (RLQs). We conducted a Chandra snapshot survey of 12 bright BAL RLQs selected from SDSS/FIRST data and possessing a wide range of radio…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-24 B. P. Miller , W. N. Brandt , R. R. Gibson , G. P. Garmire , O. Shemmer

We present $\it {ASCA}$ observations of the z=1.98 prototype BALQSO: PHL5200. The source was detected in both SIS and GIS. A power-law spectrum ($\alpha_E = 0.6^{+0.9}_{-0.6}$) with large intrinsic absorption (N$_H = 1.3^{+2.3}_{-1.1}…

Astrophysics · Physics 2007-05-23 Smita Mathur , Martin Elvis , K. P. Singh

In a spectroscopic follow-up to the VLA FIRST survey, the FIRST Bright Quasar Survey (FBQS) has found 29 radio-selected broad absorption line (BAL) quasars. This sample provides the first opportunity to study the properties of…

We present a deep ASCA observation of a Broad Absorption Line Quasar (BALQSO) PG0946+301. The source was clearly detected in one of the gas imaging spectrometers, but not in any other detector. If BALQSOs have intrinsic X-ray spectra…

The broad absorption line (BAL) features seen in a small fraction of quasar optical/UV spectra are attributed to bulk outflows away from the quasar core. Observational evidence suggests that dust plays a key role in these systems, although…

Astrophysics · Physics 2009-11-10 Geraint F. Lewis , Scott C. Chapman , Zdenka Kuncic

Using the SCUBA bolometer array on the JCMT, we have carried out a submillimetre survey of Broad Absorption Line quasars (BALQs). The sample has been chosen to match, in redshift and optical luminosity, an existing benchmark 850um sample of…

Astrophysics · Physics 2008-11-26 R. S. Priddey , S. C. Gallagher , K. G. Isaak , R. G. Sharp , R. G. McMahon , H. M. Butner

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 have discovered two low-ionization broad absorption line quasars in programs to obtain optical spectra for radio-selected quasar candidates from the VLA FIRST Survey (Becker, White, & Helfand 1995). Both belong to the extremely rare…

We present a large sample of 501 radio-selected BL Lac candidates from the combination of the Sloan Digital Sky Survey (SDSS) Data Release 5 optical spectroscopy and from the Faint Images of the Radio Sky at Twenty-Centimeters (FIRST) radio…

We present the results of an optical photometric monitoring program of 10 extremely radio loud broad absorption line quasars (RL-BALQSOs) with radio-loudness parameter, R, greater than 100 and magnitude g_i < 19. Over an observing run of…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Ravi Joshi , Hum Chand

We present the results of a multi-wavelength study of a sample of high-redshift Radio Loud (RL) Broad Absorption Line (BAL) quasars. This way we extend to higher redshift previous studies on the radio properties, and broadband optical…

Astrophysics of Galaxies · Physics 2017-04-12 D. Tuccillo , G. Bruni , M. A. DiPompeo , M. S. Brotherton , A. Pasetto , A. Kraus , J. I. Gonzalez-Serrano , K. -H. Mack

We present a spectropolarimetric survey of 36 broad absorption line quasi-stellar objects (BAL QSOs). The continuum, absorption trough, and emission line polarization of BAL QSOs yield clues about their structure. We confirm that BAL QSOs…

Astrophysics · Physics 2009-10-31 P. M. Ogle , M. H. Cohen , J. S. Miller , H. D. Tran , R. W. Goodrich , A. R. Martel

Broad absorption line quasars (BAL QSOs) belong to a class of objects not well-understood as yet. Their UV spectra show BALs in the blue wings of the UV resonance lines, owing to ionized gas with outflow velocities up to 0.2 c. They can…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-17 G. Bruni , D. Dallacasa , K. -H. Mack , F. M. Montenegro-Montes , J. I. González-Serrano , J. Holt , F. Jiménez-Luján