Slow-blue nuclear hypervariables in PanSTARRS-1
Abstract
We discuss 76 large amplitude transients (Δm > 1.5) occurring in the nuclei of galaxies, nearly all with no previously known active galactic nucleus (AGN). They have been discovered as part of the Pan-STARRS1 (PS1) 3π survey, by comparison with Sloan Digital Sky Survey (SDSS) photometry a decade earlier, and then monitored with the Liverpool Telescope, and studied spectroscopically with the William Herschel Telescope (WHT). Based on colours, light-curve shape, and spectra, these transients fall into four groups. A few are misclassified stars or objects of unknown type. Some are red/fast transients and are known or likely nuclear supernovae. A few are either radio sources or erratic variables and so likely blazars. However the majority (~66 per cent) are blue and evolve slowly, on a time-scale of years. Spectroscopy shows them to be AGN at z ~0.3 – 1.4, which must have brightened since the SDSS photometry by around an order of magnitude. It is likely that these objects were in fact AGN a decade ago, but too weak to be recognized by SDSS; they could then be classed as ‘hypervariable’ AGN. By searching the SDSS Stripe 82 quasar database, we find 15 similar objects. We discuss several possible explanationsmore »
- Authors:
-
more »
- Univ. of Edinburgh (United Kingdom)
- Univ. of Maryland, College Park, MD (United States)
- Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States)
- Durham Univ. (United Kingdom)
- Queen's Univ., Belfast, Northern Ireland (United Kingdom)
- Queen's Univ., Belfast, Northern Ireland (United Kingdom); Univ. of Cambridge (United Kingdom)
- SLAC National Accelerator Lab., Menlo Park, CA (United States)
- Univ. of Hawaii, Honolulu, HI (United States)
- Princeton Univ., Princeton, NJ (United States)
- Publication Date:
- Research Org.:
- SLAC National Accelerator Lab., Menlo Park, CA (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1349095
- Grant/Contract Number:
- AC02-76SF00515
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Additional Journal Information:
- Journal Volume: 463; Journal Issue: 1; Journal ID: ISSN 0035-8711
- Publisher:
- Royal Astronomical Society
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 79 ASTRONOMY AND ASTROPHYSICS; accretion; accretion discs; gravitational lensing: micro; galaxies: active; galaxies: nuclei; quasars: general
Citation Formats
Lawrence, A., Bruce, A. G., MacLeod, C., Gezari, S., Elvis, M., Ward, M., Smartt, S. J., Smith, K. W., Wright, D., Fraser, M., Marshall, P., Kaiser, N., Burgett, W., Magnier, E., Tonry, J., Chambers, K., Wainscoat, R., Waters, C., Price, P., Metcalfe, N., Valenti, S., Kotak, R., Mead, A., Inserra, C., Chen, T. W., and Soderberg, A. Slow-blue nuclear hypervariables in PanSTARRS-1. United States: N. p., 2016.
Web. doi:10.1093/mnras/stw1963.
Lawrence, A., Bruce, A. G., MacLeod, C., Gezari, S., Elvis, M., Ward, M., Smartt, S. J., Smith, K. W., Wright, D., Fraser, M., Marshall, P., Kaiser, N., Burgett, W., Magnier, E., Tonry, J., Chambers, K., Wainscoat, R., Waters, C., Price, P., Metcalfe, N., Valenti, S., Kotak, R., Mead, A., Inserra, C., Chen, T. W., & Soderberg, A. Slow-blue nuclear hypervariables in PanSTARRS-1. United States. https://doi.org/10.1093/mnras/stw1963
Lawrence, A., Bruce, A. G., MacLeod, C., Gezari, S., Elvis, M., Ward, M., Smartt, S. J., Smith, K. W., Wright, D., Fraser, M., Marshall, P., Kaiser, N., Burgett, W., Magnier, E., Tonry, J., Chambers, K., Wainscoat, R., Waters, C., Price, P., Metcalfe, N., Valenti, S., Kotak, R., Mead, A., Inserra, C., Chen, T. W., and Soderberg, A. Thu .
"Slow-blue nuclear hypervariables in PanSTARRS-1". United States. https://doi.org/10.1093/mnras/stw1963. https://www.osti.gov/servlets/purl/1349095.
@article{osti_1349095,
title = {Slow-blue nuclear hypervariables in PanSTARRS-1},
author = {Lawrence, A. and Bruce, A. G. and MacLeod, C. and Gezari, S. and Elvis, M. and Ward, M. and Smartt, S. J. and Smith, K. W. and Wright, D. and Fraser, M. and Marshall, P. and Kaiser, N. and Burgett, W. and Magnier, E. and Tonry, J. and Chambers, K. and Wainscoat, R. and Waters, C. and Price, P. and Metcalfe, N. and Valenti, S. and Kotak, R. and Mead, A. and Inserra, C. and Chen, T. W. and Soderberg, A.},
abstractNote = {We discuss 76 large amplitude transients (Δm > 1.5) occurring in the nuclei of galaxies, nearly all with no previously known active galactic nucleus (AGN). They have been discovered as part of the Pan-STARRS1 (PS1) 3π survey, by comparison with Sloan Digital Sky Survey (SDSS) photometry a decade earlier, and then monitored with the Liverpool Telescope, and studied spectroscopically with the William Herschel Telescope (WHT). Based on colours, light-curve shape, and spectra, these transients fall into four groups. A few are misclassified stars or objects of unknown type. Some are red/fast transients and are known or likely nuclear supernovae. A few are either radio sources or erratic variables and so likely blazars. However the majority (~66 per cent) are blue and evolve slowly, on a time-scale of years. Spectroscopy shows them to be AGN at z ~0.3 – 1.4, which must have brightened since the SDSS photometry by around an order of magnitude. It is likely that these objects were in fact AGN a decade ago, but too weak to be recognized by SDSS; they could then be classed as ‘hypervariable’ AGN. By searching the SDSS Stripe 82 quasar database, we find 15 similar objects. We discuss several possible explanations for these slow-blue hypervariables – (i) unusually luminous tidal disruption events; (ii) extinction events; (iii) changes in accretion state; and (iv) large amplitude microlensing by stars in foreground galaxies. A mixture of explanations (iii) and (iv) seems most likely. As a result, both hold promise of considerable new insight into the AGN phenomenon.},
doi = {10.1093/mnras/stw1963},
journal = {Monthly Notices of the Royal Astronomical Society},
number = 1,
volume = 463,
place = {United States},
year = {Thu Sep 08 00:00:00 EDT 2016},
month = {Thu Sep 08 00:00:00 EDT 2016}
}
Web of Science
Works referenced in this record:
The Seventh data Release of the Sloan Digital sky Survey
journal, May 2009
- Abazajian, Kevork N.; Adelman-McCarthy, Jennifer K.; Agüeros, Marcel A.
- The Astrophysical Journal Supplement Series, Vol. 182, Issue 2
A CONTINUUM OF H- TO He-RICH TIDAL DISRUPTION CANDIDATES WITH A PREFERENCE FOR E+A GALAXIES
journal, September 2014
- Arcavi, Iair; Gal-Yam, Avishay; Sullivan, Mark
- The Astrophysical Journal, Vol. 793, Issue 1
Seyfert 1 Mutation of the Classical Seyfert 2 Nucleus NGC 7582
journal, July 1999
- Aretxaga, Itziar; Joguet, B.; Kunth, D.
- The Astrophysical Journal, Vol. 519, Issue 2
Sizes and Temperature Profiles of Quasar Accretion Disks from Chromatic Microlensing
journal, February 2011
- Blackburne, Jeffrey A.; Pooley, David; Rappaport, Saul
- The Astrophysical Journal, Vol. 729, Issue 1
The Galaxy Luminosity Function and Luminosity Density at Redshift z = 0.1
journal, August 2003
- Blanton, Michael R.; Hogg, David W.; Bahcall, Neta A.
- The Astrophysical Journal, Vol. 592, Issue 2
The unusual X-ray and optical properties of the ultrasoft active galactic nucleus Zwicky 159.034 (RE J1237+264)
journal, March 1995
- Brandt, W. N.; Pounds, K. A.; Fink, H.
- Monthly Notices of the Royal Astronomical Society, Vol. 273, Issue 1
SWIFT /UVOT GRISM MONITORING OF NGC 5548 IN 2013: AN ATTEMPT AT Mg ii REVERBERATION MAPPING
journal, September 2015
- Cackett, E. M.; Gültekin, K.; Bentz, M. C.
- The Astrophysical Journal, Vol. 810, Issue 2
PTF10iya: a short-lived, luminous flare from the nuclear region of a star-forming galaxy: PTF10iya: a short-lived, luminous flare
journal, January 2012
- Cenko, S. Bradley; Bloom, Joshua S.; Kulkarni, S. R.
- Monthly Notices of the Royal Astronomical Society, Vol. 420, Issue 3
Galactic Stellar and Substellar Initial Mass Function
journal, July 2003
- Chabrier, Gilles
- Publications of the Astronomical Society of the Pacific, Vol. 115, Issue 809
PS1-10afx AT z = 1.388: PAN-STARRS1 DISCOVERY OF A NEW TYPE OF SUPERLUMINOUS SUPERNOVA
journal, April 2013
- Chornock, R.; Berger, E.; Rest, A.
- The Astrophysical Journal, Vol. 767, Issue 2
THE ULTRAVIOLET-BRIGHT, SLOWLY DECLINING TRANSIENT PS1-11af AS A PARTIAL TIDAL DISRUPTION EVENT
journal, December 2013
- Chornock, R.; Berger, E.; Gezari, S.
- The Astrophysical Journal, Vol. 780, Issue 1
Echoes of multiple outbursts of Sagittarius A ⋆ revealed by Chandra
journal, September 2013
- Clavel, M.; Terrier, R.; Goldwurm, A.
- Astronomy & Astrophysics, Vol. 558
Characteristic Ultraviolet/Optical Timescales in Active Galactic Nuclei
journal, July 2001
- Collier, Stefan; Peterson, Bradley M.
- The Astrophysical Journal, Vol. 555, Issue 2
The NRAO VLA Sky Survey
journal, May 1998
- Condon, J. J.; Cotton, W. D.; Greisen, E. W.
- The Astronomical Journal, Vol. 115, Issue 5
Structure Function Analysis of Long-Term Quasar Variability
journal, February 2005
- de Vries, W. H.; Becker, R. H.; White, R. L.
- The Astronomical Journal, Vol. 129, Issue 2
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
First Results from the Catalina Real-Time Transient Survey
journal, April 2009
- Drake, A. J.; Djorgovski, S. G.; Mahabal, A.
- The Astrophysical Journal, Vol. 696, Issue 1
Microlensing variability in the gravitationally lensed quasar QSO 2237+0305 $\mathsf{\equiv}$ the Einstein Cross: II. Energy profile of the accretion disk
journal, September 2008
- Eigenbrod, A.; Courbin, F.; Meylan, G.
- Astronomy & Astrophysics, Vol. 490, Issue 3
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
Atlas of quasar energy distributions
journal, November 1994
- Elvis, Martin; Wilkes, Belinda J.; McDowell, Jonathan C.
- The Astrophysical Journal Supplement Series, Vol. 95
The tidal disruption of a star by a massive black hole
journal, November 1989
- Evans, Charles R.; Kochanek, Christopher S.
- The Astrophysical Journal, Vol. 346
Hypercalibration: a Pan-Starrs1-Based Recalibration of the Sloan Digital sky Survey Photometry
journal, May 2016
- Finkbeiner, Douglas P.; Schlafly, Edward F.; Schlegel, David J.
- The Astrophysical Journal, Vol. 822, Issue 2
Multiplicity among M dwarfs
journal, September 1992
- Fischer, Debra A.; Marcy, Geoffrey W.
- The Astrophysical Journal, Vol. 396
UV/Optical Detections of Candidate Tidal Disruption Events by GALEX and CFHTLS
journal, April 2008
- Gezari, S.; Basa, S.; Martin, D. C.
- The Astrophysical Journal, Vol. 676, Issue 2
Luminous Thermal Flares from Quiescent Supermassive Black Holes
journal, May 2009
- Gezari, Suvi; Heckman, Tim; Cenko, S. Bradley
- The Astrophysical Journal, Vol. 698, Issue 2
An ultraviolet–optical flare from the tidal disruption of a helium-rich stellar core
journal, May 2012
- Gezari, S.; Chornock, R.; Rest, A.
- Nature, Vol. 485, Issue 7397
Long-term optical variability properties of the Palomar-Green quasars
journal, July 1999
- Giveon, Uriel; Maoz, Dan; Kaspi, Shai
- Monthly Notices of the Royal Astronomical Society, Vol. 306, Issue 3
Response functions as diagnostics of the broad-line region in active galactic nuclei
journal, July 1993
- Goad, M. R.; O'Brien, P. T.; Gondhalekar, P. M.
- Monthly Notices of the Royal Astronomical Society, Vol. 263, Issue 1
Dust in the broad-line regions of Seyfert galaxies
journal, February 1995
- Goodrich, Robert W.
- The Astrophysical Journal, Vol. 440
The GB6 Catalog of Radio Sources
journal, March 1996
- Gregory, P. C.; Scott, W. K.; Douglas, K.
- The Astrophysical Journal Supplement Series, Vol. 103
Ic 3599 did it Again: a Second Outburst of the X-Ray Transient Seyfert 1.9 Galaxy
journal, April 2015
- Grupe, Dirk; Komossa, S.; Saxton, Richard
- The Astrophysical Journal, Vol. 803, Issue 2
Hydrodynamical Simulations to Determine the Feeding rate of Black Holes by the Tidal Disruption of Stars: the Importance of the Impact Parameter and Stellar Structure
journal, March 2013
- Guillochon, James; Ramirez-Ruiz, Enrico
- The Astrophysical Journal, Vol. 767, Issue 1
Follow‐Up Chandra Observations of Three Candidate Tidal Disruption Events
journal, April 2004
- Halpern, J. P.; Gezari, S.; Komossa, S.
- The Astrophysical Journal, Vol. 604, Issue 2
Accretion Disk Instabilities, Cold Dark Matter Models, and Their Role in Quasar Evolution
journal, January 2001
- Hatziminaoglou, Evanthia; Siemiginowska, Aneta; Elvis, Martin
- The Astrophysical Journal, Vol. 547, Issue 1
Gravitational microlensing, quasar variability and missing matter
journal, November 1993
- Hawkins, M. R. S.
- Nature, Vol. 366, Issue 6452
Dark matter from quasar microlensing
journal, February 1996
- Hawkins, M. R. S.
- Monthly Notices of the Royal Astronomical Society, Vol. 278, Issue 3
Colour changes in quasar light curves
journal, September 2003
- Hawkins, M. R. S.
- Monthly Notices of the Royal Astronomical Society, Vol. 344, Issue 2
Timescale of variation and the size of the accretion disc in active galactic nuclei
journal, November 2006
- Hawkins, M. R. S.
- Astronomy & Astrophysics, Vol. 462, Issue 2
The Coevolution of Galaxies and Supermassive Black Holes: Insights from Surveys of the Contemporary Universe
journal, August 2014
- Heckman, Timothy M.; Best, Philip N.
- Annual Review of Astronomy and Astrophysics, Vol. 52, Issue 1
ASASSN-14ae: a tidal disruption event at 200 Mpc
journal, October 2014
- Holoien, T. W. -S.; Prieto, J. L.; Bersier, D.
- Monthly Notices of the Royal Astronomical Society, Vol. 445, Issue 3
SUPER-LUMINOUS TYPE Ic SUPERNOVAE: CATCHING A MAGNETAR BY THE TAIL
journal, June 2013
- Inserra, C.; Smartt, S. J.; Jerkstrand, A.
- The Astrophysical Journal, Vol. 770, Issue 2
Photometric variations in the Q2237 + 0305 system - First detection of a microlensing event
journal, December 1989
- Irwin, M. J.; Webster, R. L.; Hewett, P. C.
- The Astronomical Journal, Vol. 98
A Robust Determination of the size of Quasar Accretion Disks Using Gravitational Microlensing
journal, May 2012
- Jiménez-Vicente, J.; Mediavilla, E.; Muñoz, J. A.
- The Astrophysical Journal, Vol. 751, Issue 2
The Average size and Temperature Profile of Quasar Accretion Disks
journal, February 2014
- Jiménez-Vicente, J.; Mediavilla, E.; Kochanek, C. S.
- The Astrophysical Journal, Vol. 783, Issue 1
Stellar masses and star formation histories for 10 5 galaxies from the Sloan Digital Sky Survey
journal, May 2003
- Kauffmann, Guinevere; Heckman, Timothy M.; Simon White, D. M.
- Monthly Notices of the Royal Astronomical Society, Vol. 341, Issue 1
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
A New Cloud of Hydrogen Emission in a Bright Galactic Nucleus
journal, March 1971
- Khachikian, Edward Ye.; Weedman, Daniel W.
- The Astrophysical Journal, Vol. 164
Tidal disruption of stars by supermassive black holes: The X-ray view
journal, January 2012
- Komossa, S.
- EPJ Web of Conferences, Vol. 39
A Huge Drop in the X-Ray Luminosity of the Nonactive Galaxy RX J1242.6-1119A, and the First Postflare Spectrum: Testing the Tidal Disruption Scenario
journal, February 2004
- Komossa, Stefanie; Halpern, Jules; Schartel, Norbert
- The Astrophysical Journal, Vol. 603, Issue 1
What the Optical Recombination Lines Can Tell Us about the Broad‐Line Regions of Active Galactic Nuclei
journal, May 2004
- Korista, Kirk T.; Goad, Michael R.
- The Astrophysical Journal, Vol. 606, Issue 2
M Dwarfs in Sloan Digital sky Survey Stripe 82: Photometric Light Curves and Flare rate Analysis
journal, July 2009
- Kowalski, Adam F.; Hawley, Suzanne L.; Hilton, Eric J.
- The Astronomical Journal, Vol. 138, Issue 2
Molecular tori in Seyfert galaxies - Feeding the monster and hiding it
journal, June 1988
- Krolik, Julian H.; Begelman, Mitchell C.
- The Astrophysical Journal, Vol. 329
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 UV peak in active galactic nuclei: a false continuum from blurred reflection?: AGN UV peak: blurred reflection?
journal, May 2012
- Lawrence, A.
- Monthly Notices of the Royal Astronomical Society, Vol. 423, Issue 1
Misaligned Disks as Obscurers in Active Galaxies
journal, April 2010
- Lawrence, Andy; Elvis, Martin
- The Astrophysical Journal, Vol. 714, Issue 1
Ariel V sky survey: X-ray variability of NGC 5128
journal, November 1977
- Lawrence, A.; Pye, J. P.; Elvis, M.
- Monthly Notices of the Royal Astronomical Society, Vol. 181, Issue 1
The UKIRT Infrared Deep Sky Survey (UKIDSS)
journal, August 2007
- Lawrence, A.; Warren, S. J.; Almaini, O.
- Monthly Notices of the Royal Astronomical Society, Vol. 379, Issue 4
Bright PanSTARRS Nuclear Transients – what are they?
journal, January 2012
- Lawrence, A.; Gezari, S.; Elvis, M.
- EPJ Web of Conferences, Vol. 39
THE 4 Ms CHANDRA DEEP FIELD-SOUTH NUMBER COUNTS APPORTIONED BY SOURCE CLASS: PERVASIVE ACTIVE GALACTIC NUCLEI AND THE ASCENT OF NORMAL GALAXIES
journal, May 2012
- Lehmer, B. D.; Xue, Y. Q.; Brandt, W. N.
- The Astrophysical Journal, Vol. 752, Issue 1
Multiband light curves of tidal disruption events: Tidal disruption events
journal, September 2010
- Lodato, Giuseppe; Rossi, Elena M.
- Monthly Notices of the Royal Astronomical Society, Vol. 410, Issue 1
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
A Consistent Picture Emerges: a Compact X-Ray Continuum Emission Region in the Gravitationally Lensed Quasar sdss J0924+0219
journal, June 2015
- MacLeod, Chelsea L.; Morgan, Christopher W.; Mosquera, A.
- The Astrophysical Journal, Vol. 806, Issue 2
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 Pan-Starrs 1 Photometric Reference Ladder, Release 12.01
journal, April 2013
- Magnier, E. A.; Schlafly, E.; Finkbeiner, D.
- The Astrophysical Journal Supplement Series, Vol. 205, Issue 2
The Pan-STARRS1 Small Area Survey 2
journal, September 2013
- Metcalfe, N.; Farrow, D. J.; Cole, S.
- Monthly Notices of the Royal Astronomical Society, Vol. 435, Issue 3
J004457+4123 (Sharov 21): not a remarkable nova in M 31 but a background quasar with a spectacular UV flare
journal, March 2010
- Meusinger, H.; Henze, M.; Birkle, K.
- Astronomy and Astrophysics, Vol. 512
The Quasar Accretion disk Size-Black hole mass Relation
journal, March 2010
- Morgan, Christopher W.; Kochanek, C. S.; Morgan, Nicholas D.
- The Astrophysical Journal, Vol. 712, Issue 2
MEASURING QUASAR VARIABILITY WITH Pan-STARRS1 AND SDSS
journal, March 2014
- Morganson, E.; Burgett, W. S.; Chambers, K. C.
- The Astrophysical Journal, Vol. 784, Issue 2
The time Domain Spectroscopic Survey: Variable Selection and Anticipated Results
journal, June 2015
- Morganson, Eric; Green, Paul J.; Anderson, Scott F.
- The Astrophysical Journal, Vol. 806, Issue 2
The Microlensing Properties of a Sample of 87 Lensed Quasars
journal, August 2011
- Mosquera, A. M.; Kochanek, C. S.
- The Astrophysical Journal, Vol. 738, Issue 1
The Cosmic Lens All-Sky Survey - I. Source selection and observations
journal, May 2003
- Myers, S. T.; Jackson, N. J.; Browne, I. W. A.
- Monthly Notices of the Royal Astronomical Society, Vol. 341, Issue 1
Dust Emission from Active Galactic Nuclei
journal, May 2002
- Nenkova, Maia; Ivezić, Željko; Elitzur, Moshe
- The Astrophysical Journal, Vol. 570, Issue 1
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
EXTRAORDINARY MAGNIFICATION OF THE ORDINARY TYPE Ia SUPERNOVA PS1-10afx
journal, April 2013
- Quimby, Robert M.; Werner, Marcus C.; Oguri, Masamune
- The Astrophysical Journal, Vol. 768, Issue 1
Detection of the Gravitational Lens Magnifying a Type Ia Supernova
journal, April 2014
- Quimby, R. M.; Oguri, M.; More, A.
- Science, Vol. 344, Issue 6182
Tidal disruption of stars by black holes of 106–108 solar masses in nearby galaxies
journal, June 1988
- Rees, Martin J.
- Nature, Vol. 333, Issue 6173
Colors of 2625 Quasars at 0 < [ITAL][CLC]z[/CLC][/ITAL] < 5 Measured in the Sloan Digital Sky Survey Photometric System
journal, May 2001
- Richards, Gordon T.; Fan, Xiaohui; Schneider, Donald P.
- The Astronomical Journal, Vol. 121, Issue 5
Spectral Energy Distributions and Multiwavelength Selection of Type 1 Quasars
journal, October 2006
- Richards, Gordon T.; Lacy, Mark; Storrie‐Lombardi, Lisa J.
- The Astrophysical Journal Supplement Series, Vol. 166, Issue 2
X-Ray Echo from the Sagittarius C Complex and 500-year Activity History of Sagittarius A*
journal, April 2013
- Ryu, Syukyo Gando; Nobukawa, Masayoshi; Nakashima, Shinya
- Publications of the Astronomical Society of Japan, Vol. 65, Issue 2
Quasar microlensing
journal, April 2010
- Schmidt, R. W.; Wambsganss, J.
- General Relativity and Gravitation, Vol. 42, Issue 9
The Color Variability of Quasars
journal, December 2011
- Schmidt, Kasper B.; Rix, Hans-Walter; Shields, Joseph C.
- The Astrophysical Journal, Vol. 744, Issue 2
Variable Faint Optical Sources Discovered by Comparing the POSS and SDSS Catalogs
journal, June 2006
- Sesar, Branimir; Svilković, Domjan; Ivezić, Željko
- The Astronomical Journal, Vol. 131, Issue 6
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
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
Deriving the Quasar Luminosity Function from Accretion-Disk Instabilities
journal, June 1997
- Siemiginowska, Aneta; Elvis, Martin
- The Astrophysical Journal, Vol. 482, Issue 1
Microlensing of the broad line region in 17 lensed quasars
journal, July 2012
- Sluse, D.; Hutsemékers, D.; Courbin, F.
- Astronomy & Astrophysics, Vol. 544
PRECISE THROUGHPUT DETERMINATION OF THE PanSTARRS TELESCOPE AND THE GIGAPIXEL IMAGER USING A CALIBRATED SILICON PHOTODIODE AND A TUNABLE LASER: INITIAL RESULTS
journal, December 2010
- Stubbs, Christopher W.; Doherty, Peter; Cramer, Claire
- The Astrophysical Journal Supplement Series, Vol. 191, Issue 2
Variation of the spectrum of the Seyfert galaxy NGC 7603.
journal, December 1976
- Tholine, J. E.; Osterbrock, D. E.
- The Astrophysical Journal, Vol. 210
THE Pan-STARRS1 PHOTOMETRIC SYSTEM
journal, April 2012
- Tonry, J. L.; Stubbs, C. W.; Lykke, K. R.
- The Astrophysical Journal, Vol. 750, Issue 2
Optical Discovery of Probable Stellar Tidal Disruption Flares
journal, October 2011
- van Velzen, Sjoert; Farrar, Glennys R.; Gezari, Suvi
- The Astrophysical Journal, Vol. 741, Issue 2
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 1997 Outburst of AO 0235+164: Evidence for a Microlensing Event?
journal, July 2000
- Webb, James R.; Howard, Emily; Benítez, Erika
- The Astronomical Journal, Vol. 120, Issue 1
Galaxy Number Counts from the Sloan Digital Sky Survey Commissioning Data
journal, September 2001
- Yasuda, Naoki; Fukugita, Masataka; Narayanan, Vijay K.
- The Astronomical Journal, Vol. 122, Issue 3
The Baldwin Effect in the Narrow Emission Lines of Active Galactic Nuclei
journal, December 2012
- Zhang, Kai; Wang, Ting-Gui; Gaskell, C. Martin
- The Astrophysical Journal, Vol. 762, Issue 1
Works referencing / citing this record:
A population of highly energetic transient events in the centres of active galaxies
journal, November 2017
- Kankare, E.; Kotak, R.; Mattila, S.
- Nature Astronomy, Vol. 1, Issue 12
A new class of flares from accreting supermassive black holes
journal, January 2019
- Trakhtenbrot, Benny; Arcavi, Iair; Ricci, Claudio
- Nature Astronomy, Vol. 3, Issue 3
Results of a systematic search for outburst events in 1.4 million galaxies
journal, October 2018
- Drake, A. J.; Djorgovski, S. G.; Graham, M. J.
- Monthly Notices of the Royal Astronomical Society, Vol. 482, Issue 1
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
The Vanishing and Appearing Sources during a Century of Observations Project. I. USNO Objects Missing in Modern Sky Surveys and Follow-up Observations of a “Missing Star”
journal, December 2019
- Villarroel, Beatriz; Soodla, Johan; Comerón, Sébastien
- The Astronomical Journal, Vol. 159, Issue 1
New Physical Insights about Tidal Disruption Events from a Comprehensive Observational Inventory at X-Ray Wavelengths
journal, April 2017
- Auchettl, Katie; Guillochon, James; Ramirez-Ruiz, Enrico
- The Astrophysical Journal, Vol. 838, Issue 2
Extreme Variability Quasars from the Sloan Digital Sky Survey and the Dark Energy Survey
journal, February 2018
- Rumbaugh, N.; Shen, Yue; Morganson, Eric
- The Astrophysical Journal, Vol. 854, Issue 2
A Mid-IR Selected Changing-look Quasar and Physical Scenarios for Abrupt AGN Fading
journal, August 2018
- Stern, Daniel; McKernan, Barry; Graham, Matthew J.
- The Astrophysical Journal, Vol. 864, 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
New physical insights about Tidal Disruption Events from a comprehensive observational inventory at X-ray wavelengths
text, January 2016
- Auchettl, Katie; Guillochon, James; Ramirez-Ruiz, Enrico
- arXiv
A forward modelling approach to AGN variability -- Method description and early applications
text, January 2019
- Sartori, Lia F.; Trakhtenbrot, Benny; Schawinski, Kevin
- arXiv
The Vanishing & Appearing Sources during a Century of Observations project: I. USNO objects missing in modern sky surveys and follow-up observations of a "missing star"
text, January 2019
- Villarroel, Beatriz; Soodla, Johan; Comerón, Sébastien
- arXiv