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Title: Extreme Variability in a Broad Absorption Line Quasar

Abstract

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 five years, the source slowly brightened by approximately one magnitude, to V ∼ 16.2. Only ∼1 in 10,000 quasars show such extreme variability, as quantified by the extreme parameters derived for this quasar assuming a damped random walk model. A combination of archival and newly acquired spectra reveal the source to be an iron low-ionization broad absorption line quasar with extreme changes in its absorption spectrum. Some absorption features completely disappear over the 9 years of optical spectra, while other features remain essentially unchanged. We report the first definitive redshift for this source, based on the detection of broad H α in a Keck/MOSFIRE spectrum. Absorption systems separated by several 1000 km s{sup −1} in velocity show coordinated weakening in the depths of their troughs as the continuum flux increases. We interpret the broad absorption line variability to be due to changes in photoionization, rather than due to motion of material along our line of sight. This source highlights onemore » sort of rare transition object that astronomy will now be finding through dedicated time-domain surveys.« less

Authors:
;  [1]; ; ; ; ; ;  [2]; ;  [3];  [4];  [5]
  1. Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Mail Stop 169-221, Pasadena, CA 91109 (United States)
  2. California Institute of Technology, 1200 E. California Boulevard, Pasadena, CA 91125 (United States)
  3. Department of Physics, Virginia Tech, Blacksburg, VA 24061 (United States)
  4. Department of Physics and Astronomy, 4129 Frederick Reines Hall, University of California, Irvine, CA 92697 (United States)
  5. Department of Physics, Middlebury College, Middlebury, VT 05753 (United States)
Publication Date:
OSTI Identifier:
22663685
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 839; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABSORPTION; ABSORPTION SPECTRA; ASTRONOMY; DETECTION; GALAXIES; PHOTOIONIZATION; PHOTOMETRY; QUASARS; RANDOMNESS; RED SHIFT; VELOCITY

Citation Formats

Stern, Daniel, Jun, Hyunsung D., Graham, Matthew J., Djorgovski, S. G., Donalek, Ciro, Drake, Andrew J., Mahabal, Ashish A., Steidel, Charles C., Arav, Nahum, Chamberlain, Carter, Barth, Aaron J., and Glikman, Eilat, E-mail: daniel.k.stern@jpl.nasa.gov. Extreme Variability in a Broad Absorption Line Quasar. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA683C.
Stern, Daniel, Jun, Hyunsung D., Graham, Matthew J., Djorgovski, S. G., Donalek, Ciro, Drake, Andrew J., Mahabal, Ashish A., Steidel, Charles C., Arav, Nahum, Chamberlain, Carter, Barth, Aaron J., & Glikman, Eilat, E-mail: daniel.k.stern@jpl.nasa.gov. Extreme Variability in a Broad Absorption Line Quasar. United States. doi:10.3847/1538-4357/AA683C.
Stern, Daniel, Jun, Hyunsung D., Graham, Matthew J., Djorgovski, S. G., Donalek, Ciro, Drake, Andrew J., Mahabal, Ashish A., Steidel, Charles C., Arav, Nahum, Chamberlain, Carter, Barth, Aaron J., and Glikman, Eilat, E-mail: daniel.k.stern@jpl.nasa.gov. Thu . "Extreme Variability in a Broad Absorption Line Quasar". United States. doi:10.3847/1538-4357/AA683C.
@article{osti_22663685,
title = {Extreme Variability in a Broad Absorption Line Quasar},
author = {Stern, Daniel and Jun, Hyunsung D. and Graham, Matthew J. and Djorgovski, S. G. and Donalek, Ciro and Drake, Andrew J. and Mahabal, Ashish A. and Steidel, Charles C. and Arav, Nahum and Chamberlain, Carter and Barth, Aaron J. and Glikman, Eilat, E-mail: daniel.k.stern@jpl.nasa.gov},
abstractNote = {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 five years, the source slowly brightened by approximately one magnitude, to V ∼ 16.2. Only ∼1 in 10,000 quasars show such extreme variability, as quantified by the extreme parameters derived for this quasar assuming a damped random walk model. A combination of archival and newly acquired spectra reveal the source to be an iron low-ionization broad absorption line quasar with extreme changes in its absorption spectrum. Some absorption features completely disappear over the 9 years of optical spectra, while other features remain essentially unchanged. We report the first definitive redshift for this source, based on the detection of broad H α in a Keck/MOSFIRE spectrum. Absorption systems separated by several 1000 km s{sup −1} in velocity show coordinated weakening in the depths of their troughs as the continuum flux increases. We interpret the broad absorption line variability to be due to changes in photoionization, rather than due to motion of material along our line of sight. This source highlights one sort of rare transition object that astronomy will now be finding through dedicated time-domain surveys.},
doi = {10.3847/1538-4357/AA683C},
journal = {Astrophysical Journal},
number = 2,
volume = 839,
place = {United States},
year = {Thu Apr 20 00:00:00 EDT 2017},
month = {Thu Apr 20 00:00:00 EDT 2017}
}