Results 91 to 100 of about 16,078 (195)

Acceleration and Substructure Constraints in a Quasar Outflow

, 2007
We present observations of probable line-of-sight acceleration of a broad absorption trough of C IV in the quasar SDSS J024221.87+004912.6. We also discuss how the velocity overlap of two other outflowing systems in the same object constrains the ...
Alireza Rafiee, Barlow T., Bromage G., Damien Hutsemekers, John E. Everett, Leighly K. M., Patrick B. Hall, Robbins H. E., Sarah I. Sadavoy, Shakura N. I., Smith L. J.   +10 more
core   +1 more source

Discovery of a Classic FR-II Broad Absorption Line Quasar from the FIRST Survey

, 2000
We have discovered a remarkable quasar, FIRST J101614.3+520916, whose optical spectrum shows unambiguous broad absorption features while its double-lobed radio morphology and luminosity clearly indicate a classic Fanaroff-Riley Type II radio source.
Fanaroff B., Mark Lacy, Michael D. Gregg, Michael S. Brotherton, Richard L. White, Robert H. Becker, Sally A. Laurent‐Muehleisen, Scheuer P. A. G., Wright A. E.   +8 more
core   +1 more source

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) Quasar Survey: Quasar Properties from Data Releases 10 to 12

The Astrophysical Journal Supplement Series
We present the quasar catalog from Data Releases 10 to 12 of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) Quasar Survey, comprising quasars observed between 2021 September and 2024 June. We robustly identified 11,346 quasars, of
Bing Lyu, Xue-Bing Wu, Jun-Jie Jin, Yuming Fu, Yuxuan Pang, Huimei Wang, Rui Zhu, Su Yao, Yan-Li Ai, Yan-xia Zhang, Hai-long Yuan, Zhi-ying Huo   +11 more
doaj   +1 more source

X-ray observations of broad absorption-line quasars

The Astrophysical Journal, 1984
The present 0.1-4 keV observer frame data was obtained for three broad absorption-line quasars with the imaging proportional counter on the Einstein Observatory. Data for one object, UM 232, are sufficiently good to tell that absorption at 1 keV is unimportant (quasar rest frame), which leads to an upper limit to the column density of absorbing gas of ...
openaire   +1 more source

Peculiar Broad Absorption Line Quasars found in DPOSS

, 2003
With the recent release of large (i.e., > hundred million objects), well-calibrated photometric surveys, such as DPOSS, 2MASS, and SDSS, spectroscopic identification of important targets is no longer a simple issue. In order to enhance the returns from a spectroscopic survey, candidate sources are often preferentially selected to be of interest ...
Brunner, Robert J., Hall, Patrick B., Djorgovski, S. George, Gal, R. R., Mahabal, A. A., Lopes, P. A. A., de Carvalho, R. R., Odewahn, S. C., Castro, S., Thompson, D., Chaffee, F., Darling, J., Desai, V.   +12 more
openaire   +2 more sources

A strong redshift dependence of the broad absorption line quasar fraction

, 2010
We describe the application of non-negative matrix factorisation to generate compact reconstructions of quasar spectra from the Sloan Digital Sky Survey (SDSS), with particular reference to broad absorption line quasars (BALQSOs).
Becker, Becker, Begelman, Blanton, Cardelli, Casebeer, Chiu, Dai, Elvis, Fan, Farrah, Faucher-Giguère, Gabel, Gallagher, Ganguly, Gibson, Gibson, Glikman, Gordon T. Richards, Hall, Hamann, Hamann, Hewett, Hewett, Hewett, Hopkins, Hopkins, James T. Allen, Knigge, Lawrence, Lee, Lee, Lundgren, Lupton, Lípari, Maddox, Maiolino, Moe, Montenegro-Montes, Natasha Maddox, Paul C. Hewett, Priddey, Prochaska, Proga, Proga, Reichard, Reichard, Richards, Risaliti, Scaringi, Schlegel, Schneider, Schneider, Songaila, Sprayberry, Steinhardt, Trump, Urrutia, Vasily Belokurov, Voit, Warren, Weymann, Weymann, Wild, York   +64 more
core   +1 more source

Broad Absorption Line Variability in Radio-Loud Quasars

, 2012
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 (SDSS) or other archival data, we generate a total set of 50 pairs of BAL equivalent width measurements ...
Miller, B. P., Welling, C. A., Brandt, W. N., Gibson, R. R.   +3 more
openaire   +2 more sources

The Physical Driver of the Optical Eigenvector 1 in Quasar Main Sequence

Frontiers in Astronomy and Space Sciences, 2017
Quasars are complex sources, characterized by broad band spectra from radio through optical to X-ray band, with numerous emission and absorption features. This complexity leads to rich diagnostics.
Swayamtrupta Panda, Swayamtrupta Panda, Bożena Czerny, Bożena Czerny, Conor Wildy   +4 more
doaj   +1 more source

The Origins of a Rich Absorption Line Complex in a Quasar at Redshift 3.45

, 2010
We discuss the nature and origin of a rich complex of narrow absorption lines in the quasar J102325.31+514251.0 at redshift 3.447. We measure nine C IV(\lambda1548,1551) absorption line systems with velocities from -1400 to -6200 km/s, and full widths at
Aldcroft, Anderson, Arav, Arav, Arnaud, Barlow, Bergeron, Braun, Dietrich, D’Odorico, Elvis, Falomo, Ferland, Foltz, Fox, Fred Hamann, Gabel, Ganguly, Ganguly, Ganguly, Ganguly, Ganguly, Gibson, Grevesse, Hamann, Hamann, Hamann, Hamann, Hamann, Hamann, Hartquist, Heckman, Hopkins, Hutsemékers, Jiang, Juarez, Korista, Kuraszkiewicz, Leah E. Simon, Misawa, Misawa, Moe, Nagao, Narayanan, Nestor, Pentericci, Petitjean, Popesso, Prochaska, Prochaska, Pérez-González, Ramos Almeida, Richards, Ruiz, Ruiz, Rupke, Schaye, Shen, Simon, Srianand, Steidel, Trump, Tytler, Tzanavaris, Veilleux, Vestergaard, Vestergaard, Warner, Weymann, Weymann, Wild   +70 more
core   +1 more source

Compact radio-loud broad absorption line quasars

, 2008
For a long time, radio-loud Broad Absorption Line Quasars (BAL QSOs) were thought to be extremely rare objects. The absorbing troughs seen in their optical spectra are due to strong winds which probably have their origin within the inner region of the AGN, as a result of the accretion processes. Their radio emission constitutes an additional diagnostic
Montenegro-Montes, Francisco M., Mack, Karl-Heinz, Vigotti, Mario, Benn, Chris R., Carballo Fidalgo, Ruth, González Serrano, José Ignacio, Holt, Joanna, Jiménez Luján, Florencia   +7 more
openaire   +1 more source