Extreme Variability Quasars from the Sloan Digital Sky Survey and the Dark Energy Survey
Abstract
We perform a systematic search for long-term extreme variability quasars (EVQs) in the overlapping Sloan Digital Sky Survey and 3 Year Dark Energy Survey imaging, which provide light curves spanning more than 15 years. We identified ~1000 EVQs with a maximum change in g-band magnitude of more than 1 mag over this period, about 10% of all quasars searched. The EVQs have L bol ~ 1045–1047 erg s-1 and L/L Edd ~ 0.01–1. Accounting for selection effects, we estimate an intrinsic EVQ fraction of ~30%–50% among all $$g\lesssim 22$$ quasars over a baseline of ~15 yr. We performed detailed multi-wavelength, spectral, and variability analyses for the EVQs and compared them to their parent quasar sample. We found that EVQs are distinct from a control sample of quasars matched in redshift and optical luminosity: (1) their UV broad emission lines have larger equivalent widths; (2) their Eddington ratios are systematically lower; and (3) they are more variable on all timescales. The intrinsic difference in quasar properties for EVQs suggests that internal processes associated with accretion are the main driver for the observed extreme long-term variability. However, despite their different properties, EVQs seem to be in the tail of a continuous distribution of quasar properties, rather than standing out as a distinct population. We speculate that EVQs are normal quasars accreting at relatively low rates, where the accretion flow is more likely to experience instabilities that drive the changes in flux by a factor of a few on multi-year timescales.
- Authors:
-
;
;
;
;
;
more »
- Publication Date:
- Research Org.:
- SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Brookhaven National Laboratory (BNL), Upton, NY (United States); Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), High Energy Physics (HEP)
- Contributing Org.:
- DES Collaboration
- OSTI Identifier:
- 1425676
- Alternate Identifier(s):
- OSTI ID: 1389253; OSTI ID: 1409080; OSTI ID: 1435204
- Report Number(s):
- BNL-114280-2017-JA; FERMILAB-PUB-17-211-AE; arXiv:1706.07875
Journal ID: ISSN 1538-4357; TRN: US1802147
- Grant/Contract Number:
- AC02-76SF00515; AST-1138766; AYA2012-39559; ESP2013-48274; FPA2013-47986; 240672; 291329; 306478; SC0012704; AC02-07CH11359; AC05-00OR22725
- Resource Type:
- Accepted Manuscript
- Journal Name:
- The Astrophysical Journal (Online)
- Additional Journal Information:
- Journal Name: The Astrophysical Journal (Online); Journal Volume: 854; Journal Issue: 2; Journal ID: ISSN 1538-4357
- Publisher:
- Institute of Physics (IOP)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 79 ASTRONOMY AND ASTROPHYSICS; black hole physics; galaxies: active; line: profiles; quasars: general; surveys
Citation Formats
Rumbaugh, N., Shen, Yue, Morganson, Eric, Liu, Xin, Banerji, M., McMahon, R. G., Abdalla, F. B., Benoit-Lévy, A., Bertin, E., Brooks, D., Buckley-Geer, E., Capozzi, D., Carnero Rosell, A., Carrasco Kind, M., Carretero, J., Cunha, C. E., D’Andrea, C. B., da Costa, L. N., DePoy, D. L., Desai, S., Doel, P., Frieman, J., García-Bellido, J., Gruen, D., Gruendl, R. A., Gschwend, J., Gutierrez, G., Honscheid, K., James, D. J., Kuehn, K., Kuhlmann, S., Kuropatkin, N., Lima, M., Maia, M. A. G., Marshall, J. L., Martini, P., Menanteau, F., Plazas, A. A., Reil, K., Roodman, A., Sanchez, E., Scarpine, V., Schindler, R., Schubnell, M., Sheldon, E., Smith, M., Soares-Santos, M., Sobreira, F., Suchyta, E., Swanson, M. E. C., Walker, A. R., and Wester, W.. Extreme Variability Quasars from the Sloan Digital Sky Survey and the Dark Energy Survey. United States: N. p., 2018.
Web. doi:10.3847/1538-4357/aaa9b6.
Rumbaugh, N., Shen, Yue, Morganson, Eric, Liu, Xin, Banerji, M., McMahon, R. G., Abdalla, F. B., Benoit-Lévy, A., Bertin, E., Brooks, D., Buckley-Geer, E., Capozzi, D., Carnero Rosell, A., Carrasco Kind, M., Carretero, J., Cunha, C. E., D’Andrea, C. B., da Costa, L. N., DePoy, D. L., Desai, S., Doel, P., Frieman, J., García-Bellido, J., Gruen, D., Gruendl, R. A., Gschwend, J., Gutierrez, G., Honscheid, K., James, D. J., Kuehn, K., Kuhlmann, S., Kuropatkin, N., Lima, M., Maia, M. A. G., Marshall, J. L., Martini, P., Menanteau, F., Plazas, A. A., Reil, K., Roodman, A., Sanchez, E., Scarpine, V., Schindler, R., Schubnell, M., Sheldon, E., Smith, M., Soares-Santos, M., Sobreira, F., Suchyta, E., Swanson, M. E. C., Walker, A. R., & Wester, W.. Extreme Variability Quasars from the Sloan Digital Sky Survey and the Dark Energy Survey. United States. https://doi.org/10.3847/1538-4357/aaa9b6
Rumbaugh, N., Shen, Yue, Morganson, Eric, Liu, Xin, Banerji, M., McMahon, R. G., Abdalla, F. B., Benoit-Lévy, A., Bertin, E., Brooks, D., Buckley-Geer, E., Capozzi, D., Carnero Rosell, A., Carrasco Kind, M., Carretero, J., Cunha, C. E., D’Andrea, C. B., da Costa, L. N., DePoy, D. L., Desai, S., Doel, P., Frieman, J., García-Bellido, J., Gruen, D., Gruendl, R. A., Gschwend, J., Gutierrez, G., Honscheid, K., James, D. J., Kuehn, K., Kuhlmann, S., Kuropatkin, N., Lima, M., Maia, M. A. G., Marshall, J. L., Martini, P., Menanteau, F., Plazas, A. A., Reil, K., Roodman, A., Sanchez, E., Scarpine, V., Schindler, R., Schubnell, M., Sheldon, E., Smith, M., Soares-Santos, M., Sobreira, F., Suchyta, E., Swanson, M. E. C., Walker, A. R., and Wester, W.. Wed .
"Extreme Variability Quasars from the Sloan Digital Sky Survey and the Dark Energy Survey". United States. https://doi.org/10.3847/1538-4357/aaa9b6. https://www.osti.gov/servlets/purl/1425676.
@article{osti_1425676,
title = {Extreme Variability Quasars from the Sloan Digital Sky Survey and the Dark Energy Survey},
author = {Rumbaugh, N. and Shen, Yue and Morganson, Eric and Liu, Xin and Banerji, M. and McMahon, R. G. and Abdalla, F. B. and Benoit-Lévy, A. and Bertin, E. and Brooks, D. and Buckley-Geer, E. and Capozzi, D. and Carnero Rosell, A. and Carrasco Kind, M. and Carretero, J. and Cunha, C. E. and D’Andrea, C. B. and da Costa, L. N. and DePoy, D. L. and Desai, S. and Doel, P. and Frieman, J. and García-Bellido, J. and Gruen, D. and Gruendl, R. A. and Gschwend, J. and Gutierrez, G. and Honscheid, K. and James, D. J. and Kuehn, K. and Kuhlmann, S. and Kuropatkin, N. and Lima, M. and Maia, M. A. G. and Marshall, J. L. and Martini, P. and Menanteau, F. and Plazas, A. A. and Reil, K. and Roodman, A. and Sanchez, E. and Scarpine, V. and Schindler, R. and Schubnell, M. and Sheldon, E. and Smith, M. and Soares-Santos, M. and Sobreira, F. and Suchyta, E. and Swanson, M. E. C. and Walker, A. R. and Wester, W.},
abstractNote = {We perform a systematic search for long-term extreme variability quasars (EVQs) in the overlapping Sloan Digital Sky Survey and 3 Year Dark Energy Survey imaging, which provide light curves spanning more than 15 years. We identified ~1000 EVQs with a maximum change in g-band magnitude of more than 1 mag over this period, about 10% of all quasars searched. The EVQs have L bol ~ 1045–1047 erg s-1 and L/L Edd ~ 0.01–1. Accounting for selection effects, we estimate an intrinsic EVQ fraction of ~30%–50% among all $g\lesssim 22$ quasars over a baseline of ~15 yr. We performed detailed multi-wavelength, spectral, and variability analyses for the EVQs and compared them to their parent quasar sample. We found that EVQs are distinct from a control sample of quasars matched in redshift and optical luminosity: (1) their UV broad emission lines have larger equivalent widths; (2) their Eddington ratios are systematically lower; and (3) they are more variable on all timescales. The intrinsic difference in quasar properties for EVQs suggests that internal processes associated with accretion are the main driver for the observed extreme long-term variability. However, despite their different properties, EVQs seem to be in the tail of a continuous distribution of quasar properties, rather than standing out as a distinct population. We speculate that EVQs are normal quasars accreting at relatively low rates, where the accretion flow is more likely to experience instabilities that drive the changes in flux by a factor of a few on multi-year timescales.},
doi = {10.3847/1538-4357/aaa9b6},
journal = {The Astrophysical Journal (Online)},
number = 2,
volume = 854,
place = {United States},
year = {2018},
month = {2}
}
Free Publicly Available Full Text
Publisher's Version of Record
Other availability
Search WorldCat to find libraries that may hold this journal
Cited by: 54 works
Citation information provided by
Web of Science
Web of Science
Figures / Tables:
Figure 1: The g band magnitude change between the first and second extrema is plotted versus the corresponding change in g − i, so that a positive ∆g indicates a decrease in brightness. The red points are the selected EVQs. For quasars at all levels of variability, we see amore »
All figures and tables
(17 total)
Save to My Library
You must Sign In or Create an Account in order to save documents to your library.
Works referenced in this record:
The Sloan Digital Sky Survey Photometric Camera
journal, December 1998
- Gunn, J. E.; Carr, M.; Rockosi, C.
- The Astronomical Journal, Vol. 116, Issue 6
A systematic search for changing-look quasars in SDSS
journal, January 2016
- MacLeod, Chelsea L.; Ross, Nicholas P.; Lawrence, Andy
- Monthly Notices of the Royal Astronomical Society, Vol. 457, Issue 1
The Ensemble Photometric Variability of ∼25,000 Quasars in the Sloan Digital Sky Survey
journal, February 2004
- Vanden Berk, Daniel E.; Wilhite, Brian C.; Kron, Richard G.
- The Astrophysical Journal, Vol. 601, Issue 2
The [CLC][ITAL]u[/ITAL][/CLC][arcmin]′[CLC][ITAL]g[/ITAL][/CLC][arcmin]′[CLC][ITAL]r[/ITAL][/CLC][arcmin]′[CLC][ITAL]i[/ITAL][/CLC][arcmin]′[CLC][ITAL]z[/ITAL][/CLC][arcmin]′ Standard-Star System
journal, April 2002
- Smith, J. Allyn; Tucker, Douglas L.; Kent, Stephen
- The Astronomical Journal, Vol. 123, Issue 4
The Multi-Object, Fiber-Fed Spectrographs for the Sloan Digital sky Survey and the Baryon Oscillation Spectroscopic Survey
journal, July 2013
- Smee, Stephen A.; Gunn, James E.; Uomoto, Alan
- The Astronomical Journal, Vol. 146, Issue 2
The Sloan Digital Sky Survey Photometric System
journal, April 1996
- Fukugita, M.; Ichikawa, T.; Gunn, J. E.
- The Astronomical Journal, Vol. 111
Spectral analysis of four ‘hypervariable’ AGN: a micro-needle in the haystack?
journal, January 2017
- Bruce, A.; Lawrence, A.; MacLeod, C.
- Monthly Notices of the Royal Astronomical Society
Astrometric Calibration of the Sloan Digital Sky Survey
journal, March 2003
- Pier, Jeffrey R.; Munn, Jeffrey A.; Hindsley, Robert B.
- The Astronomical Journal, Vol. 125, Issue 3
The Sloan Digital Sky Survey monitor telescope pipeline
journal, November 2006
- Tucker, D. L.; Kent, S.; Richmond, M. W.
- Astronomische Nachrichten, Vol. 327, Issue 9
The Pan-STARRS wide-field optical/NIR imaging survey
conference, July 2010
- Kaiser, Nick; Burgett, William; Chambers, Ken
- SPIE Astronomical Telescopes + Instrumentation, SPIE Proceedings
The Close AGN Reference Survey (CARS): What is causing Mrk 1018’s return to the shadows after 30 years?⋆
journal, September 2016
- Husemann, B.; Urrutia, T.; Tremblay, G. R.
- Astronomy & Astrophysics, Vol. 593
The Sloan Digital Sky Survey: Technical Summary
journal, September 2000
- York, Donald G.; Adelman, J.; Anderson, Jr., John E.
- The Astronomical Journal, Vol. 120, Issue 3
EDDINGTON RATIO GOVERNS THE EQUIVALENT WIDTH OF Mg II EMISSION LINE IN ACTIVE GALACTIC NUCLEI
journal, August 2009
- Dong, Xiao-Bo; Wang, Ting-Gui; Wang, Jian-Guo
- The Astrophysical Journal, Vol. 703, Issue 1
A Large Sample of bl lac Objects from the sdss and First
journal, May 2008
- Plotkin, Richard M.; Anderson, Scott F.; Hall, Patrick B.
- The Astronomical Journal, Vol. 135, Issue 6
Dust in the broad-line regions of Seyfert galaxies
journal, February 1995
- Goodrich, Robert W.
- The Astrophysical Journal, Vol. 440
Revisiting the Unified Model of Active Galactic Nuclei
journal, August 2015
- Netzer, Hagai
- Annual Review of Astronomy and Astrophysics, Vol. 53, Issue 1
Mid-infrared Variability of Changing-look AGNs
journal, August 2017
- Sheng, Zhenfeng; Wang, Tinggui; Jiang, Ning
- The Astrophysical Journal, Vol. 846, Issue 1
The diversity of quasars unified by accretion and orientation
journal, September 2014
- Shen, Yue; Ho, Luis C.
- Nature, Vol. 513, Issue 7517
A tidal disruption flare in a massive galaxy? Implications for the fuelling mechanisms of nuclear black holes
journal, July 2015
- Merloni, A.; Dwelly, T.; Salvato, M.
- Monthly Notices of the Royal Astronomical Society, Vol. 452, Issue 1
Optically Selected bl Lacertae Candidates from the Sloan Digital sky Survey data Release Seven
journal, January 2010
- Plotkin, Richard M.; Anderson, Scott F.; Brandt, W. N.
- The Astronomical Journal, Vol. 139, Issue 2
Slow-blue nuclear hypervariables in PanSTARRS-1
journal, August 2016
- Lawrence, A.; Bruce, A. G.; MacLeod, C.
- Monthly Notices of the Royal Astronomical Society, Vol. 463, Issue 1
The detection and X-ray view of the changing look AGN HE 1136-2304
journal, June 2016
- Parker, M. L.; Komossa, S.; Kollatschny, W.
- Monthly Notices of the Royal Astronomical Society, Vol. 461, Issue 2
The 2.5 m Telescope of the Sloan Digital Sky Survey
journal, April 2006
- Gunn, James E.; Siegmund, Walter A.; Mannery, Edward J.
- The Astronomical Journal, Vol. 131, Issue 4
Exploring the Variable Sky with the Sloan Digital Sky Survey
journal, October 2007
- Sesar, Branimir; Ivezić, Željko; Lupton, Robert H.
- The Astronomical Journal, Vol. 134, Issue 6
Quasar emission lines as probes of orientation: implications for disc wind geometries and unification
journal, January 2017
- Matthews, J. H.; Knigge, C.; Long, K. S.
- Monthly Notices of the Royal Astronomical Society
SDSS data management and photometric quality assessment
journal, October 2004
- Ivezi?, ?.; Lupton, R. H.; Schlegel, D.
- Astronomische Nachrichten, Vol. 325, Issue 6-8
The 13th Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-IV Survey Mapping Nearby Galaxies at Apache Point Observatory
journal, December 2017
- Albareti, Franco D.; Prieto, Carlos Allende; Almeida, Andres
- The Astrophysical Journal Supplement Series, Vol. 233, Issue 2
Unified Schemes for Radio-Loud Active Galactic Nuclei
journal, June 1995
- Urry, C. Megan; Padovani, Paolo
- Publications of the Astronomical Society of the Pacific, Vol. 107
Spectroscopic Target Selection in the Sloan Digital Sky Survey: The Quasar Sample
journal, June 2002
- Richards, Gordon T.; Fan, Xiaohui; Newberg, Heidi Jo
- The Astronomical Journal, Vol. 123, Issue 6
The dark energy survey and operations: years 1 to 3
conference, July 2016
- Diehl, H. T.; Neilsen, E.; Gruendl, R.
- SPIE Astronomical Telescopes + Instrumentation, SPIE Proceedings
Weak line Quasars at high Redshift: Extremely high Accretion Rates or Anemic Broad-Line Regions?
journal, September 2010
- Shemmer, Ohad; Trakhtenbrot, Benny; Anderson, Scott F.
- The Astrophysical Journal, Vol. 722, Issue 2
Slim accretion disks
journal, September 1988
- Abramowicz, M. A.; Czerny, B.; Lasota, J. P.
- The Astrophysical Journal, Vol. 332
Optimal Time-Series Selection of Quasars
journal, February 2011
- Butler, Nathaniel R.; Bloom, Joshua S.
- The Astronomical Journal, Vol. 141, Issue 3
Insight into “Changing-look” AGN Mrk 1018 from the Fe K α Line: The Reprocessing Gas Has Yet to Fully Respond to the Fading of the AGN
journal, April 2017
- LaMassa, Stephanie M.; Yaqoob, Tahir; Kilgard, Roy
- The Astrophysical Journal, Vol. 840, Issue 1
Eigenvector 1: An Optimal Correlation Space for Active Galactic Nuclei
journal, June 2000
- Sulentic, J. W.; Zwitter, T.; Marziani, P.
- The Astrophysical Journal, Vol. 536, Issue 1
SPECTRAL VARIABILITY OF FIRST BRIGHT QSOs WITH SLOAN DIGITAL SKY SURVEY OBSERVATIONS
journal, October 2012
- Bian, Wei-Hao; Zhang, Li; Green, Richard
- The Astrophysical Journal, Vol. 759, Issue 2
Hubble Space Telescope STIS Ultraviolet Spectral Evidence of Outflow in Extreme Narrow‐Line Seyfert 1 Galaxies. II. Modeling and Interpretation
journal, August 2004
- Leighly, Karen M.
- The Astrophysical Journal, Vol. 611, Issue 1
The dark Energy Camera
journal, October 2015
- Flaugher, B.; Diehl, H. T.; Honscheid, K.
- The Astronomical Journal, Vol. 150, Issue 5
Unified Models for Active Galactic Nuclei and Quasars
journal, September 1993
- Antonucci, Robert
- Annual Review of Astronomy and Astrophysics, Vol. 31, Issue 1
Black Hole Mass and Eddington Ratio as Drivers for the Observable Properties of Radio‐loud and Radio‐quiet QSOs
journal, January 2002
- Boroson, Todd A.
- The Astrophysical Journal, Vol. 565, Issue 1
The Discovery of a High-Redshift Quasar without Emission Lines from Sloan Digital Sky Survey Commissioning Data
journal, December 1999
- Fan, Xiaohui; Strauss, Michael A.; Gunn, James E.
- The Astrophysical Journal, Vol. 526, Issue 2
A Catalog of 1.4 GHz Radio Sources from the FIRST Survey
journal, February 1997
- White, Richard L.; Becker, Robert H.; Helfand, David J.
- The Astrophysical Journal, Vol. 475, Issue 2
Long-term variability of the optical spectra of NGC 4151: II. Evolution of the broad H α and H β emission-line profiles
journal, November 2009
- Shapovalova, A. I.; Popović, L. Č.; Burenkov, A. N.
- Astronomy and Astrophysics, Vol. 509
Thick accretion disks around black holes and the UV/soft X-ray excess in quasars
journal, April 1988
- Madau, Piero
- The Astrophysical Journal, Vol. 327
A Catalog of Quasar Properties from Sloan Digital sky Survey data Release 7
journal, June 2011
- Shen, Yue; Richards, Gordon T.; Strauss, Michael A.
- The Astrophysical Journal Supplement Series, Vol. 194, Issue 2
Spectrophotometry of Seyfert 1 galaxies
journal, August 1977
- Osterbrock, D. E.
- The Astrophysical Journal, Vol. 215
Evolution of broad-line emission from active galactic nuclei
journal, January 2014
- Elitzur, Moshe; Ho, Luis C.; Trump, Jonathan R.
- Monthly Notices of the Royal Astronomical Society, Vol. 438, Issue 4
The XMM-Newton long look of NGC 1365: uncovering of the obscured X-ray source
journal, February 2009
- Risaliti, G.; Salvati, M.; Elvis, M.
- Monthly Notices of the Royal Astronomical Society: Letters, Vol. 393, Issue 1
iPTF Discovery of the Rapid “Turn-on” of a Luminous Quasar
journal, January 2017
- Gezari, S.; Hung, T.; Cenko, S. B.
- The Astrophysical Journal, Vol. 835, Issue 2
On the Relationship between Radio Emission and Black Hole Mass in Galactic Nuclei
journal, January 2002
- Ho, Luis C.
- The Astrophysical Journal, Vol. 564, Issue 1
Understanding extreme quasar optical variability with CRTS – I. Major AGN flares
journal, June 2017
- Graham, Matthew J.; Djorgovski, S. G.; Drake, Andrew J.
- Monthly Notices of the Royal Astronomical Society, Vol. 470, Issue 4
A Photometricity and Extinction Monitor at the Apache Point Observatory
journal, October 2001
- Hogg, David W.; Finkbeiner, Douglas P.; Schlegel, David J.
- The Astronomical Journal, Vol. 122, Issue 4
An Efficient Targeting Strategy for Multiobject Spectrograph Surveys: the Sloan Digital Sky Survey “Tiling” Algorithm
journal, April 2003
- Blanton, Michael R.; Lin, Huan; Lupton, Robert H.
- The Astronomical Journal, Vol. 125, Issue 4
Changing look: from Compton-thick to Compton-thin, or the rebirth of fossil active galactic nuclei
journal, June 2003
- Matt, G.; Guainazzi, M.; Maiolino, R.
- Monthly Notices of the Royal Astronomical Society, Vol. 342, Issue 2
Sdss-Iii: Massive Spectroscopic Surveys of the Distant Universe, the Milky way, and Extra-Solar Planetary Systems
journal, August 2011
- Eisenstein, Daniel J.; Weinberg, David H.; Agol, Eric
- The Astronomical Journal, Vol. 142, Issue 3
The emission-line properties of low-redshift quasi-stellar objects
journal, May 1992
- Boroson, Todd A.; Green, Richard F.
- The Astrophysical Journal Supplement Series, Vol. 80
Continuum and Emission‐Line Strength Relations for a Large Active Galactic Nuclei Sample
journal, December 2002
- Dietrich, M.; Hamann, F.; Shields, J. C.
- The Astrophysical Journal, Vol. 581, Issue 2
Parsec-scale radio morphology and variability of a changing-look AGN: the case of Mrk 590
journal, April 2016
- Koay, J. Y.; Vestergaard, M.; Bignall, H. E.
- Monthly Notices of the Royal Astronomical Society, Vol. 460, Issue 1
Unification of Luminous type 1 Quasars Through c iv Emission
journal, April 2011
- Richards, Gordon T.; Kruczek, Nicholas E.; Gallagher, S. C.
- The Astronomical Journal, Vol. 141, Issue 5
Now you see it, now you don't: the disappearing central engine of the quasar J1011+5442
journal, November 2015
- Runnoe, Jessie C.; Cales, Sabrina; Ruan, John J.
- Monthly Notices of the Royal Astronomical Society, Vol. 455, Issue 2
The Sloan Digital sky Survey Quasar Catalog. v. Seventh data Release
journal, April 2010
- Schneider, Donald P.; Richards, Gordon T.; Hall, Patrick B.
- The Astronomical Journal, Vol. 139, Issue 6
The Wide-Field Infrared Survey Explorer (Wise): Mission Description and Initial On-Orbit Performance
journal, November 2010
- Wright, Edward L.; Eisenhardt, Peter R. M.; Mainzer, Amy K.
- The Astronomical Journal, Vol. 140, Issue 6
Polarization of the changing-look quasar J1011+5442
journal, July 2017
- Hutsemékers, D.; Agís González, B.; Sluse, D.
- Astronomy & Astrophysics, Vol. 604
Time development of the emission lines and continuum of NGC 4151
journal, August 1983
- Antonucci, R. R. J.; Cohen, R. D.
- The Astrophysical Journal, Vol. 271
Dependence of the Optical/Ultraviolet Variability on the Emission-Line Properties and Eddington Ratio in Active Galactic Nuclei
journal, May 2010
- Ai, Y. L.; Yuan, W.; Zhou, H. Y.
- The Astrophysical Journal, Vol. 716, Issue 1
THE SLOAN DIGITAL SKY SURVEY COADD: 275 deg 2 OF DEEP SLOAN DIGITAL SKY SURVEY IMAGING ON STRIPE 82
journal, September 2014
- Annis, James; Soares-Santos, Marcelle; Strauss, Michael A.
- The Astrophysical Journal, Vol. 794, Issue 2
THE TYPECASTING OF ACTIVE GALACTIC NUCLEI: Mrk 590 NO LONGER FITS THE ROLE
journal, November 2014
- Denney, K. D.; De Rosa, G.; Croxall, K.
- The Astrophysical Journal, Vol. 796, Issue 2
High-Redshift sdss Quasars with weak Emission Lines
journal, June 2009
- Diamond-Stanic, Aleksandar M.; Fan, Xiaohui; Brandt, W. N.
- The Astrophysical Journal, Vol. 699, Issue 1
The Dark Energy Survey
journal, June 2005
- Flaugher, Brenna
- International Journal of Modern Physics A, Vol. 20, Issue 14
The Optical Variability of sdss Quasars from Multi-Epoch Spectroscopy. ii. Color Variation
journal, April 2016
- Guo (郭恒潇), Hengxiao; Gu, Minfeng
- The Astrophysical Journal, Vol. 822, Issue 1
Iron Opacity bump Changes the Stability and Structure of Accretion Disks in Active Galactic Nuclei
journal, August 2016
- Jiang(姜燕飞), Yan-Fei; Davis, Shane W.; Stone, James M.
- The Astrophysical Journal, Vol. 827, Issue 1
A Global Three-Dimensional Radiation Magneto-Hydrodynamic Simulation of Super-Eddington Accretion Disks
journal, November 2014
- Jiang, Yan-Fei; Stone, James M.; Davis, Shane W.
- The Astrophysical Journal, Vol. 796, Issue 2
Are the Variations in Quasar Optical flux Driven by Thermal Fluctuations?
journal, May 2009
- Kelly, Brandon C.; Bechtold, Jill; Siemiginowska, Aneta
- The Astrophysical Journal, Vol. 698, Issue 1
REVISITING STOCHASTIC VARIABILITY OF AGNs WITH STRUCTURE FUNCTIONS
journal, July 2016
- Kozłowski, Szymon
- The Astrophysical Journal, Vol. 826, Issue 2
Quantifying Quasar Variability as part of a General Approach to Classifying Continuously Varying Sources
journal, December 2009
- Kozłowski, Szymon; Kochanek, Christopher S.; Udalski, A.
- The Astrophysical Journal, Vol. 708, Issue 2
The Discovery of the First “Changing Look” Quasar: new Insights into the Physics and Phenomenology of Active Galactic Nuclei
journal, February 2015
- LaMassa, Stephanie M.; Cales, Sabrina; Moran, Edward C.
- The Astrophysical Journal, Vol. 800, Issue 2
THE 31 DEG 2 RELEASE OF THE STRIPE 82 X-RAY SURVEY: THE POINT SOURCE CATALOG
journal, February 2016
- LaMassa, Stephanie M.; Urry, C. Megan; Cappelluti, Nico
- The Astrophysical Journal, Vol. 817, Issue 2
X-Ray Insights into the Nature of phl 1811 Analogs and weak Emission-Line Quasars: Unification with a Geometrically Thick Accretion Disk?
journal, May 2015
- Luo, B.; Brandt, W. N.; Hall, P. B.
- The Astrophysical Journal, Vol. 805, Issue 2
Modeling the time Variability of sdss Stripe 82 Quasars as a Damped Random walk
journal, September 2010
- MacLeod, C. L.; Ivezić, Ž.; Kochanek, C. S.
- The Astrophysical Journal, Vol. 721, Issue 2
A Description of Quasar Variability Measured Using Repeated sdss and poss Imaging
journal, June 2012
- MacLeod, Chelsea L.; Ivezić, Željko; Sesar, Branimir
- The Astrophysical Journal, Vol. 753, Issue 2
An evolutionary link between Seyfert I and II galaxies?
journal, November 1984
- Penston, M. V.; Pérez, Enrique
- Monthly Notices of the Royal Astronomical Society, Vol. 211, Issue 1
Toward an Understanding of Changing-Look Quasars: an Archival Spectroscopic Search in sdss
journal, July 2016
- Ruan, John J.; Anderson, Scott F.; Cales, Sabrina L.
- The Astrophysical Journal, Vol. 826, Issue 2
BROAD H β EMISSION-LINE VARIABILITY IN A SAMPLE OF 102 LOCAL ACTIVE GALAXIES
journal, April 2016
- Runco, Jordan N.; Cosens, Maren; Bennert, Vardha N.
- The Astrophysical Journal, Vol. 821, Issue 1
Selecting Quasars by Their Intrinsic Variability
journal, April 2010
- Schmidt, Kasper B.; Marshall, Philip J.; Rix, Hans-Walter
- The Astrophysical Journal, Vol. 714, Issue 2
The man Behind the Curtain: X-Rays Drive the uv Through nir Variability in the 2013 Active Galactic Nucleus Outburst in ngc 2617
journal, May 2014
- Shappee, B. J.; Prieto, J. L.; Grupe, D.
- The Astrophysical Journal, Vol. 788, Issue 1
Weak Emission-Line Quasars in the Context of a Modified Baldwin Effect
journal, May 2015
- Shemmer, Ohad; Lieber, Sara
- The Astrophysical Journal, Vol. 805, Issue 2
Self-Shadowing Effects of slim Accretion Disks in Active Galactic Nuclei: the Diverse Appearance of the Broad-Line Region
journal, November 2014
- Wang, Jian-Min; Qiu, Jie; Du, Pu
- The Astrophysical Journal, Vol. 797, Issue 1
A Population of X-Ray weak Quasars: phl 1811 Analogs at high Redshift
journal, July 2011
- Wu, Jianfeng; Brandt, W. N.; Hall, Patrick B.
- The Astrophysical Journal, Vol. 736, Issue 1
The Dark Energy Survey
conference, January 2006
- Sánchez, E.
- THE DARK SIDE OF THE UNIVERSE: 2nd International Conference on The Dark Side of the Universe DSU 2006, AIP Conference Proceedings
The detection and X-ray view of the changing look AGN HE 1136-2304
text, January 2016
- Parker, Ml; Komossa, S.; Kollatschny, W.
- Apollo - University of Cambridge Repository
Slow-blue nuclear hypervariables in PanSTARRS-1
text, January 2016
- Lawrence, A.; Bruce, A. G.; MacLeod, C.
- Apollo - University of Cambridge Repository
The Dark Energy Survey
conference, May 2012
- Sevilla, Ignacio
- Proceedings of XXIst International Europhysics Conference on High Energy Physics — PoS(EPS-HEP2011)
The Close AGN Reference Survey (CARS): Mrk 1018 returns to the shadows after 30 years as a Seyfert 1
journal, September 2016
- McElroy, R. E.; Husemann, B.; Croom, S. M.
- Astronomy & Astrophysics, Vol. 593
The 13th Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-IV Survey Mapping Nearby Galaxies at Apache Point Observatory
text, January 2017
- Albareti, Fd; Prieto, Ca; Almeida, A.
- Apollo - University of Cambridge Repository
The 13th Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-IV Survey Mapping Nearby Galaxies at Apache Point Observatory
text, January 2017
- Albareti, Franco D.; Allende Prieto, Carlos; Almeida, Andres
- Apollo - University of Cambridge Repository
Exploring the Variable Sky with the Sloan Digital Sky Survey
text, January 2007
- Sesar, Branimir; Ivezic, Zeljko; Lupton, Robert H.
- arXiv
The XMM-Newton long look of NGC 1365: uncovering of the obscured X-ray source
text, January 2008
- Risaliti, G.; Salvati, M.; Elvis, M.
- arXiv
Optically Selected BL Lacertae Candidates from the Sloan Digital Sky Survey Data Release Seven
text, January 2009
- Plotkin, Richard M.; Anderson, S. F.; Brandt, W. N.
- arXiv
Selecting Quasars by their Intrinsic Variability
text, January 2010
- Schmidt, Kasper B.; Marshall, Philip J.; Rix, Hans-Walter
- arXiv
The Sloan Digital Sky Survey Quasar Catalog V. Seventh Data Release
text, January 2010
- Schneider, Donald P.; Richards, Gordon T.; Hall, Patrick B.
- arXiv
Dependence of the optical/UV variability on the emission line properties and Eddington ratio in active galactic nuclei
text, January 2010
- Ai, Y. L.; Yuan, W.; Zhou, H. Y.
- arXiv
The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
text, January 2010
- Wright, Edward L.; Eisenhardt, Peter R. M.; Mainzer, Amy
- arXiv
Optimal Time-Series Selection of Quasars
text, January 2010
- Butler, Nathaniel R.; Bloom, Joshua S.
- arXiv
Unification of Luminous Type 1 Quasars through CIV Emission
text, January 2010
- Richards, Gordon T.; Kruczek, Nicholas E.; Gallagher, S. C.
- arXiv
A Population of X-ray Weak Quasars: PHL 1811 Analogs at High Redshift
text, January 2011
- Wu, Jianfeng; Brandt, W. N.; Hall, Patrick B.
- arXiv
A Description of Quasar Variability Measured Using Repeated SDSS and POSS Imaging
text, January 2011
- MacLeod, Chelsea L.; Ivezic, Zeljko; Sesar, Branimir
- arXiv
X-ray Insights into the Nature of PHL 1811 Analogs and Weak Emission-Line Quasars: Unification with a Geometrically Thick Accretion Disk?
text, January 2015
- Luo, B.; Brandt, W. N.; Hall, P. B.
- arXiv
A tidal disruption flare in a massive galaxy? Implications for the fuelling mechanisms of nuclear black holes
text, January 2015
- Merloni, A.; Dwelly, T.; Salvato, M.
- arXiv
The 31 Deg$^2$ Release of the Stripe 82 X-ray Survey: The Point Source Catalog
text, January 2015
- LaMassa, Stephanie M.; Urry, C. Megan; Cappelluti, Nico
- arXiv
The optical variability of SDSS quasars from multi-epoch spectroscopy. II. color variation
text, January 2016
- Guo, Hengxiao; Gu, Minfeng
- arXiv
Revisiting Stochastic Variability of AGNs with Structure Functions
text, January 2016
- Kozłowski, Szymon
- arXiv
The detection and X-ray view of the changing look AGN HE 1136-2304
text, January 2016
- Parker, M. L.; Komossa, S.; Kollatschny, W.
- arXiv
The Close AGN Reference Survey (CARS) - What is causing Mrk1018's return to the shadows after 30 years?
text, January 2016
- Husemann, B.; Urrutia, T.; Tremblay, G. R.
- arXiv
iPTF Discovery of the Rapid "Turn On" of a Luminous Quasar
text, January 2016
- Gezari, S.; Hung, T.; Cenko, S. B.
- arXiv
Insight Into "Changing-Look" AGN Mrk 1018 from the Fe K$α$ Line: The Reprocessing Gas Has Yet to Fully Respond to the Fading of the AGN
text, January 2017
- LaMassa, Stephanie M.; Yaqoob, Tahir; Kilgard, Roy
- arXiv
Mid-infrared variability of changing-look AGN
text, January 2017
- Sheng, Zhenfeng; Wang, Tinggui; Jiang, Ning
- arXiv
A photometricity and extinction monitor at the Apache Point Observatory
text, January 2001
- Hogg, David W.; Finkbeiner, Douglas P.; Schlegel, David J.
- arXiv
The Ensemble Photometric Variability of ~25000 Quasars in the Sloan Digital Sky Survey
text, January 2003
- Berk, D. E. Vanden; Wilhite, B. C.; Kron, R. G.
- arXiv
SDSS Data Management and Photometric Quality Assessment
text, January 2004
- Ivezic, Z.; Lupton, R. H.; Schlegel, D.
- arXiv
The 2.5 m Telescope of the Sloan Digital Sky Survey
text, January 2006
- Gunn, James E.; Siegmund, Walter A.; al, Edward J. Mannery et
- arXiv
The Sloan Digital Sky Survey Photometric Camera
text, January 1998
- Gunn, J.; Carr, M.; Rockosi, C.
- arXiv
The Discovery of a High-redshift Quasar without Emission Lines from Sloan Digital Sky Survey Commissioning Data
text, January 1999
- Collaboration, Sdss; Fan, Xiaohui
- arXiv
Works referencing / citing this record:
A model for AGN variability on multiple time-scales
journal, February 2018
- Sartori, Lia F.; Schawinski, Kevin; Trakhtenbrot, Benny
- Monthly Notices of the Royal Astronomical Society: Letters, Vol. 476, Issue 1
The Ensemble Photometric Variability of Over 10 5 Quasars in the Dark Energy Camera Legacy Survey and the Sloan Digital Sky Survey
journal, June 2018
- Li, Zefeng; McGreer, Ian D.; Wu, Xue-Bing
- The Astrophysical Journal, Vol. 861, Issue 1
The Sloan Digital Sky Survey Reverberation Mapping Project: Accretion and Broad Emission Line Physics from a Hypervariable Quasar
journal, October 2019
- Dexter, Jason; Xin, Shuo; Shen, Yue
- The Astrophysical Journal, Vol. 885, Issue 1
Initial Results from a Systematic Search for Changing-look Active Galactic Nuclei Selected via Mid-infrared Variability
journal, January 2020
- Sheng, Zhenfeng; Wang, Tinggui; Jiang, Ning
- The Astrophysical Journal, Vol. 889, Issue 1
A new physical interpretation of optical and infrared variability in quasars
journal, July 2018
- Ross, Nicholas P.; Ford, K. E. Saavik; Graham, Matthew
- Monthly Notices of the Royal Astronomical Society, Vol. 480, Issue 4
A New Class of Changing-look LINERs
journal, September 2019
- Frederick, Sara; Gezari, Suvi; Graham, Matthew J.
- The Astrophysical Journal, Vol. 883, Issue 1
Discovery of an Mg ii Changing-look Active Galactic Nucleus and Its Implications for a Unification Sequence of Changing-look Active Galactic Nuclei
journal, October 2019
- Guo, Hengxiao; Sun, Mouyuan; Liu, Xin
- The Astrophysical Journal, Vol. 883, Issue 2
Spectral energy distributions of candidate periodically variable quasars: testing the binary black hole hypothesis
journal, December 2019
- Guo, Hengxiao; Liu, Xin; Tayyaba, Zafar
- Monthly Notices of the Royal Astronomical Society, Vol. 492, Issue 2
HST/COS observations of the newly discovered obscuring outflow in NGC 3783
journal, December 2018
- Kriss, G. A.; Mehdipour, M.; Kaastra, J. S.
- Astronomy & Astrophysics, Vol. 621
Understanding Broad Mg ii Variability in Quasars with Photoionization: Implications for Reverberation Mapping and Changing-look Quasars
journal, January 2020
- Guo, Hengxiao; Shen, Yue; He, Zhicheng
- The Astrophysical Journal, Vol. 888, Issue 2
Changing-look Quasar Candidates: First Results from Follow-up Spectroscopy of Highly Optically Variable Quasars
journal, March 2019
- MacLeod, Chelsea L.; Green, Paul J.; Anderson, Scott F.
- The Astrophysical Journal, Vol. 874, Issue 1
A Forward Modeling Approach to AGN Variability--Method Description and Early Applications
journal, September 2019
- Sartori, Lia F.; Trakhtenbrot, Benny; Schawinski, Kevin
- The Astrophysical Journal, Vol. 883, Issue 2
WISE view of narrow-line Seyfert 1 galaxies: mid-infrared colour and variability
journal, November 2018
- Rakshit, Suvendu; Johnson, Ansu; Stalin, C. S.
- Monthly Notices of the Royal Astronomical Society, Vol. 483, Issue 2
Discovery of 21 New Changing-look AGNs in the Northern Sky
journal, July 2018
- Yang, Qian; Wu, Xue-Bing; Fan, Xiaohui
- The Astrophysical Journal, Vol. 862, Issue 2
Extreme AGN variability: evidence of magnetically elevated accretion?
journal, November 2018
- Dexter, Jason; Begelman, Mitchell C.
- Monthly Notices of the Royal Astronomical Society: Letters, Vol. 483, Issue 1
NuSTAR Perspective on High-redshift MeV Blazars
journal, February 2020
- Marcotulli, L.; Paliya, V.; Ajello, M.
- The Astrophysical Journal, Vol. 889, Issue 2
Observational Nonstationarity of AGN Variability: The Only Way to Go Is Down!
journal, January 2020
- Caplar, Neven; Pena, Theodore; Johnson, Sean D.
- The Astrophysical Journal, Vol. 889, Issue 2
The ‘Big Dipper’: the nature of the extreme variability of the AGN SDSS J2232−0806
journal, February 2019
- Kynoch, Daniel; Ward, Martin J.; Lawrence, Andy
- Monthly Notices of the Royal Astronomical Society, Vol. 485, Issue 2
Two New “Turn-off” Changing-look Active Galactic Nuclei and Implication on “Partially Obscured” AGNs
journal, December 2019
- Wang, J.; Xu, D. W.; Wang, Y.
- The Astrophysical Journal, Vol. 887, Issue 1
An Unusual Mid-infrared Flare in a Type 2 AGN: An Obscured Turning-on AGN or Tidal Disruption Event?
journal, November 2019
- Yang, Qian; Shen, Yue; Liu, Xin
- The Astrophysical Journal, Vol. 885, Issue 2
NuSTAR perspective on high-redshift MeV blazars
text, January 2020
- Marcotulli, L.; Paliya, Vaidehi Sharan; Ajello, M.
- Deutsches Elektronen-Synchrotron, DESY, Hamburg
A model for AGN variability on multiple timescales
text, January 2018
- Sartori, Lia F.; Schawinski, Kevin; Trakhtenbrot, Benny
- arXiv
A new physical interpretation of optical and infrared variability in quasars
text, January 2018
- Ross, Nicholas P.; Ford, K. E. Saavik; Graham, Matthew
- arXiv
The ensemble photometric variability of over $10^5$ quasars in the Dark Energy Camera Legacy Survey and the Sloan Digital Sky Survey
text, January 2018
- Li, Zefeng; McGreer, Ian D.; Wu, Xue-Bing
- arXiv
Changing-Look Quasar Candidates: First Results from Follow-up Spectroscopy of Highly Optically Variable Quasars
text, January 2018
- MacLeod, Chelsea L.; Green, Paul J.; Anderson, Scott F.
- arXiv
HST/COS observations of the newly discovered obscuring outflow in NGC 3783
text, January 2018
- Kriss, G. A.; Mehdipour, M.; Kaastra, J. S.
- arXiv
WISE view of Narrow-Line Seyfert 1 galaxies: mid-infrared color and variability
text, January 2018
- Rakshit, Suvendu; Johnson, Ansu; Stalin, C. S.
- arXiv
Initial results from a systematic search for changing-look active galactic nuclei selected via mid-infrared variability
text, January 2019
- Sheng, Zhenfeng; Wang, Tinggui; Jiang, Ning
- arXiv
The Sloan Digital Sky Survey Reverberation Mapping Project: Accretion and Broad Emission Line Physics from a Hypervariable Quasar
text, January 2019
- Dexter, Jason; Xin, Shuo; Shen, Yue
- arXiv
Understanding Broad Mg II Variability in Quasars with Photoionization: Implications for Reverberation Mapping and Changing-Look Quasars
text, January 2019
- Guo, Hengxiao; Shen, Yue; He, Zhicheng
- arXiv
Spectral Energy Distributions of Candidate Periodically-Variable Quasars: Testing the Binary Black Hole Hypothesis
text, January 2019
- Guo, Hengxiao; Liu, Xin; Tayyaba, Zafar
- arXiv
A forward modelling approach to AGN variability -- Method description and early applications
text, January 2019
- Sartori, Lia F.; Trakhtenbrot, Benny; Schawinski, Kevin
- arXiv
Observational nonstationarity of AGN variability: The only way to go is down!
text, January 2020
- Caplar, Neven; Pena, Theodore; Johnson, Sean D.
- arXiv
Figures / Tables found in this record:
Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.