English
Related papers

Related papers: Probing the time variability of five Fe low broad …

200 papers

We present results of our time variability studies of Mg II and Al III absorption lines in a sample of 22 Low Ionization Broad Absorption Line QSOs (LoBAL QSOs) at 0.2 <= zem <= 2.1 using the 2m telescope at IUCAA Girawali Observatory over…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 M. Vivek , R. Srianand , P. Petitjean , V. Mohan , A. Mahabal , S. Samui

FeLoBALs are a rare class of quasar outflows with low-ionization broad absorption lines (BALs), large column densities, and potentially large kinetic energies that might be important for `feedback' to galaxy evolution. In order to probe the…

Astrophysics of Galaxies · Physics 2015-09-09 S. M. McGraw , J. C. Shields , F. W. Hamann , D. M. Capellupo , S. C. Gallagher , W. N. Brandt

We present the variability study of broad absorption lines (BALs) in a uniformly radio-selected sample of 28 BAL quasars using the archival data from the FIRST Bright Quasar Survey (FBQS) and the Sloan Digital Sky Survey (SDSS), as well as…

Astrophysics of Galaxies · Physics 2015-04-17 Shaohua Zhang , Hongyan Zhou , Tinggui Wang , Huiyuan Wang , Xiheng Shi , Bo Liu , Wenjuan Liu , Zhenzhen Li , Shufen Wang

The physical properties and dynamical behavior of Broad Absorption Line (BAL) outflows are crucial themes in understanding the connections between galactic centers and their hosts. FeLoBALs (identified with the presence of low-ionization Fe…

We study the dramatic decrease in iron absorption strength in the iron low-ionization broad absorption line quasar SDSS J084133.15+200525.8. We report on the continued weakening of absorption in the prototype of this class of variable broad…

Astrophysics of Galaxies · Physics 2016-05-04 Alireza Rafiee , Patrik Pirkola , Patrick B. Hall , Natalee Galati , Jesse Rogerson , Abtin Ameri

We present Suzaku observations of three iron low-ionization broad absorption line quasars (FeLoBALs). We detect J1723+5553 (3\sigma) in the observed 2--10 keV band, and constrain its intrinsic nh column density to nh > 6\times10^{23} \cmsq…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Leah K. Morabito , Xinyu Dai , Karen M. Leighly , Gregory R. Sivakoff , Francesco Shankar

CRTS J084133.15+200525.8 is an optically bright quasar at z=2.345 that has shown extreme spectral variability over the past decade. Photometrically, the source had a visual magnitude of V~17.3 between 2002 and 2008. Then, over the following…

We have observed a dramatic change in the spectrum of the formerly heavily absorbed `overlapping-trough' iron low-ionization broad absorption line (FeLoBAL) quasar FBQS J1408+3054. Over a time span of between 0.6 to 5 rest-frame years, the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Patrick B. Hall , Konstantin Anosov , R. L. White , W. N. Brandt , M. D. Gregg , R. R. Gibson , R. H. Becker , D. P. Schneider

We report sensitive Chandra X-ray non-detections of two unusual, luminous Iron Low-Ionization Broad Absorption Line Quasars (FeLoBALs). The observations do detect a non-BAL, wide-binary companion quasar to one of the FeLoBAL quasars. We…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-17 Jesse A. Rogerson , Patrick B. Hall , Stephanie A. Snedden , Michael S. Brotherton , Scott F. Anderson

We present a multi-epoch spectroscopic study of the broad absorption line (BAL) quasar J115636.82+085628.9 (z(em) = 2.1077), based on five spectra spanning nearly two decades in the observer's frame. This source exhibits remarkable…

Astrophysics of Galaxies · Physics 2025-08-05 P. Aromal , R. Srianand , S. C. Gallagher , M. Vivek , P. Petitjean

We show for the first time that FBQS J1151+3822 is an iron low-ionization broad absorption line quasar (FeLoBAL QSO), the second-brightest and second-closest known example of this class. He I* and Fe II together act as an effective…

Astrophysics of Galaxies · Physics 2014-02-18 Adrian B. Lucy , Karen M. Leighly , Donald M. Terndrup , Matthias Dietrich , Sarah C. Gallagher

SDSS J083942.11+380526.3 is an Iron Low-ionization Broad Absorption Line (FeLoBAL) quasar at z = 2.3, and Aoki et al. (2006) recently found the presence of an H alpha absorption line in the broad H alpha emission line. Motivated by an idea…

We present the optical-near infrared spectral energy distributions (SED) and near infrared variability properties of 30 low-redshift iron low-ionization Broad Absorption Line quasars (FeLoBALQs) and matched samples of LoBALQs and unabsorbed…

Among the unusual broad absorption line quasars being found by the Sloan Digital Sky Survey (SDSS) are objects with much stronger absorption in Fe III than Fe II. These unusual line ratios require a high density in the outflow (n_H >= 3 x…

Astrophysics · Physics 2007-05-23 Patrick B. Hall , Damien Hutsemekers

We use quantitative metrics to characterize the variation of CIV 1549 A broad absorption lines (BALs) over 3--6 (rest-frame) years in a sample of 13 quasars at 1.7 <= z <= 2.8 and compare the results to previous studies of BAL variability…

Astrophysics · Physics 2009-11-13 Robert R. Gibson , W. N. Brandt , Donald P. Schneider , S. C. Gallagher

We report the results of analysis of the Hbeta emission-line region of a sample of thirty low-redshift (z<1) iron low-ionization broad absorption line quasars (FeLoBALQs). Eleven of these objects are newly classified as FeLoBALQs. A matched…

The variability of broad absorption lines is investigated for a sample of 188 broad-absorption-line (BAL) quasars (QSOs) ($z > 1.7$) with at least two-epoch observations from the Sloan Digital Sky Survey Data Release 7 (SDSS DR7), covering…

Astrophysics of Galaxies · Physics 2015-11-04 Zhi-Cheng He , Wei-Hao Bian , Xiao-Lei Jiang , Xue Ge

In an ongoing infrared imaging survey of quasars at Keck Observatory, we have discovered that the z=1.285 quasar SDSS J233646.2-010732.6 comprises two point sources with a separation of 1.67". Resolved spectra show that one component is a…

The variability of the broad absorption lines is investigated for a broad absorption line (BAL) QSO, SDSS J022844.09+000217.0 (z = 2.719), with 18 SDSS/BOSS spectra covering 4128 days in the observed frame. With the ratio of the rms…

Astrophysics of Galaxies · Physics 2016-10-05 Zhi-Cheng He , Wei-Hao Bian , Xiao-Lei Jiang , Yue-Feng Wang

With a 1999 ASCA observation, PG2112+059 became notable as the first Broad Absorption Line (BAL) quasar found to exhibit a typical radio-quiet quasar X-ray continuum underlying a large amount of intrinsic absorption. We present a recent…

Astrophysics · Physics 2009-11-10 S. C. Gallagher , W. N. Brandt , Beverley J. Wills , J. C. Charlton , G. Chartas , A. Laor
‹ Prev 1 2 3 10 Next ›