DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Continuum Reverberation Mapping of the Accretion Disks in Two Seyfert 1 Galaxies

Abstract

We present optical continuum lags for two Seyfert 1 galaxies, MCG+08-11-011 and NGC 2617, using monitoring data from a reverberation mapping campaign carried out in 2014. Our light curves span the ugriz filters over four months, with median cadences of 1.0 and 0.6 days for MCG+08-11-011 and NGC 2617, respectively, combined with roughly daily X-ray and near-UV data from Swift for NGC 2617. We find lags consistent with geometrically thin accretion-disk models that predict a lag-wavelength relation of τ ∝ λ 4/3. However, the observed lags are larger than predictions based on standard thin-disk theory by factors of 3.3 for MCG+08-11-011 and 2.3 for NGC 2617. Furthermore, these differences can be explained if the mass accretion rates are larger than inferred from the optical luminosity by a factor of 4.3 in MCG+08-11-011 and a factor of 1.3 in NGC 2617, although uncertainty in the SMBH masses determines the significance of this result. While the X-ray variability in NGC 2617 precedes the UV/optical variability, the long (2.6 day) lag is problematic for coronal reprocessing models.

Authors:
 [1];  [2]; ORCiD logo [2]; ORCiD logo [3];  [4]; ORCiD logo [5];  [6]; ORCiD logo [7]; ORCiD logo [8]; ORCiD logo [3];  [9];  [10]; ORCiD logo [11]; ORCiD logo [7];  [12];  [13]; ORCiD logo [14];  [15];  [16]; ORCiD logo [3] more »; ORCiD logo [17]; ORCiD logo [3]; ORCiD logo [18]; ORCiD logo [6];  [17]; ORCiD logo [19];  [20]; ORCiD logo [10]; ORCiD logo [3];  [15];  [21];  [3];  [22]; ORCiD logo [23];  [3]; ORCiD logo [16];  [15];  [24];  [17];  [25];  [26]; ORCiD logo [3];  [15];  [13];  [17];  [13]; ORCiD logo [27];  [5]; ORCiD logo [28];  [29]; ORCiD logo [3];  [3];  [30];  [31];  [32]; ORCiD logo [33]; ORCiD logo [34];  [13]; ORCiD logo [35];  [3]; ORCiD logo [36]; ORCiD logo [20];  [3]; ORCiD logo [3]; ORCiD logo [37]; ORCiD logo [38];  [35]; ORCiD logo [3]; ORCiD logo [39];  [40]; ORCiD logo [41];  [3] « less
  1. The Ohio State Univ., Columbus, OH (United States); MIT Kavli Institute for Space and Astrophysics Research, Cambridge, MA (United States)
  2. Univ. of St. Andrews, Scotland (United Kingdom)
  3. The Ohio State Univ., Columbus, OH (United States)
  4. The Ohio State Univ., Columbus, OH (United States); Space Telescope Science Institute, Baltimore, MD (United States)
  5. Georgia State Univ., Atlanta, GA (United States)
  6. llumination Works LLC., Dublin, OH (United States)
  7. The Pennsylvania State Univ., University Park, PA (United States)
  8. Morehead State Univ., Morehead, KY (United States)
  9. Space Telescope Science Inst., Baltimore, MD (United States)
  10. California Inst. of Technology (CalTech), Pasadena, CA (United States)
  11. Univ. of California, Irvine, CA (United States)
  12. Univ. of Wyoming, Laramie, WY (United States); Sul Ross State Univ., Alpine, TX (United States)
  13. Crimean Astrophysical Observatory, Crimea (Russia)
  14. Las Cumbres Global Telescope Network, Santa Barbara, CA (United States)
  15. Southwestern Univ., Georgetown, TX (United States)
  16. Univ. of Missouri, Columbia, MO (United States)
  17. Univ. of Wyoming, Laramie, WY (United States)
  18. South African Astronomical Observatory, Cape Town (South Africa)
  19. The Pennsylvania State Univ., University Park, PA (United States); Georgia Inst. of Technology, Atlanta, GA (United States)
  20. Brigham Young Univ., Provo, UT (United States)
  21. Tel Aviv Univ., Tel Aviv (Israel)
  22. Univ. of Melbourne, Parkville, VIC (Australia)
  23. Columbia Univ., New York, NY (United States)
  24. Space Telescope Science Institute, Baltimore, MD (United States)
  25. Univ. dell’Insubria, Como (Italy)
  26. United States Naval Academy, Annapolis, MD (United States)
  27. Australian National Univ., Canberra, ACT (Australia)
  28. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States)
  29. Univ. of California, Irvine, CA (United States); Univ. of Illinois at Urbana-Champaign, Urbana, IL (United States)
  30. Univ. of Haifa, Haifa (Israel)
  31. Univ. of Missouri, Columbia, MO (United States); Southern African Large Telescope Foundation, Cape Town (South Africa)
  32. The Pennsylvania State Univ., University Park, PA (United States); Univ. of Michigan, Ann Arbor, MI (United States)
  33. Texas Tech Univ., Lubbock, TX (United States)
  34. Univ. Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil)
  35. Carnegie Observatories, Pasadena, CA (United States)
  36. Vanderbilt Univ., Nashville, TN (United States)
  37. Univ. of California, Los Angeles, CA (United States)
  38. Univ. of California, Davis, CA (United States)
  39. Univ. of Bath, Bath (United Kingdom)
  40. Technion, Haifa (Israel)
  41. Univ. of Johannesburg, Auckland Park (South Africa)
Publication Date:
Research Org.:
Krell Institute, Ames, IA (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1542018
Grant/Contract Number:  
FG02-97ER25308
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; Astronomy & Astrophysics; accretion; accretion disks; galaxies: individual(MCG+08-11-011, NGC 2617); galaxies: Seyfer

Citation Formats

Fausnaugh, M. M., Starkey, D. A., Horne, Keith, Kochanek, C. S., Peterson, B. M., Bentz, M. C., Denney, K. D., Grier, C. J., Grupe, D., Pogge, R. W., De Rosa, G., Adams, S. M., Barth, A. J., Beatty, Thomas G., Bhattacharjee, A., Borman, G. A., Boroson, T. A., Bottorff, M. C., Brown, Jacob E., Brown, Jonathan S., Brotherton, M. S., Coker, C. T., Crawford, S. M., Croxall, K. V., Eftekharzadeh, Sarah, Eracleous, Michael, Joner, M. D., Henderson, C. B., Holoien, T. W. -S., Hutchison, T., Kaspi, Shai, Kim, S., King, Anthea L., Li, Miao, Lochhaas, Cassandra, Ma, Zhiyuan, MacInnis, F., Manne-Nicholas, E. R., Mason, M., Montuori, Carmen, Mosquera, Ana, Mudd, Dale, Musso, R., Nazarov, S. V., Nguyen, M. L., Okhmat, D. N., Onken, Christopher A., Ou-Yang, B., Pancoast, A., Pei, L., Penny, Matthew T., Poleski, Radosław, Rafter, Stephen, Romero-Colmenero, E., Runnoe, Jessie, Sand, David J., Schimoia, Jaderson S., Sergeev, S. G., Shappee, B. J., Simonian, Gregory V., Somers, Garrett, Spencer, M., Stevens, Daniel J., Tayar, Jamie, Treu, T., Valenti, Stefano, Van Saders, J., Villanueva, Jr., S., Villforth, C., Weiss, Yaniv, Winkler, H., and Zhu, W. Continuum Reverberation Mapping of the Accretion Disks in Two Seyfert 1 Galaxies. United States: N. p., 2018. Web. doi:10.3847/1538-4357/aaaa2b.
Fausnaugh, M. M., Starkey, D. A., Horne, Keith, Kochanek, C. S., Peterson, B. M., Bentz, M. C., Denney, K. D., Grier, C. J., Grupe, D., Pogge, R. W., De Rosa, G., Adams, S. M., Barth, A. J., Beatty, Thomas G., Bhattacharjee, A., Borman, G. A., Boroson, T. A., Bottorff, M. C., Brown, Jacob E., Brown, Jonathan S., Brotherton, M. S., Coker, C. T., Crawford, S. M., Croxall, K. V., Eftekharzadeh, Sarah, Eracleous, Michael, Joner, M. D., Henderson, C. B., Holoien, T. W. -S., Hutchison, T., Kaspi, Shai, Kim, S., King, Anthea L., Li, Miao, Lochhaas, Cassandra, Ma, Zhiyuan, MacInnis, F., Manne-Nicholas, E. R., Mason, M., Montuori, Carmen, Mosquera, Ana, Mudd, Dale, Musso, R., Nazarov, S. V., Nguyen, M. L., Okhmat, D. N., Onken, Christopher A., Ou-Yang, B., Pancoast, A., Pei, L., Penny, Matthew T., Poleski, Radosław, Rafter, Stephen, Romero-Colmenero, E., Runnoe, Jessie, Sand, David J., Schimoia, Jaderson S., Sergeev, S. G., Shappee, B. J., Simonian, Gregory V., Somers, Garrett, Spencer, M., Stevens, Daniel J., Tayar, Jamie, Treu, T., Valenti, Stefano, Van Saders, J., Villanueva, Jr., S., Villforth, C., Weiss, Yaniv, Winkler, H., & Zhu, W. Continuum Reverberation Mapping of the Accretion Disks in Two Seyfert 1 Galaxies. United States. https://doi.org/10.3847/1538-4357/aaaa2b
Fausnaugh, M. M., Starkey, D. A., Horne, Keith, Kochanek, C. S., Peterson, B. M., Bentz, M. C., Denney, K. D., Grier, C. J., Grupe, D., Pogge, R. W., De Rosa, G., Adams, S. M., Barth, A. J., Beatty, Thomas G., Bhattacharjee, A., Borman, G. A., Boroson, T. A., Bottorff, M. C., Brown, Jacob E., Brown, Jonathan S., Brotherton, M. S., Coker, C. T., Crawford, S. M., Croxall, K. V., Eftekharzadeh, Sarah, Eracleous, Michael, Joner, M. D., Henderson, C. B., Holoien, T. W. -S., Hutchison, T., Kaspi, Shai, Kim, S., King, Anthea L., Li, Miao, Lochhaas, Cassandra, Ma, Zhiyuan, MacInnis, F., Manne-Nicholas, E. R., Mason, M., Montuori, Carmen, Mosquera, Ana, Mudd, Dale, Musso, R., Nazarov, S. V., Nguyen, M. L., Okhmat, D. N., Onken, Christopher A., Ou-Yang, B., Pancoast, A., Pei, L., Penny, Matthew T., Poleski, Radosław, Rafter, Stephen, Romero-Colmenero, E., Runnoe, Jessie, Sand, David J., Schimoia, Jaderson S., Sergeev, S. G., Shappee, B. J., Simonian, Gregory V., Somers, Garrett, Spencer, M., Stevens, Daniel J., Tayar, Jamie, Treu, T., Valenti, Stefano, Van Saders, J., Villanueva, Jr., S., Villforth, C., Weiss, Yaniv, Winkler, H., and Zhu, W. Fri . "Continuum Reverberation Mapping of the Accretion Disks in Two Seyfert 1 Galaxies". United States. https://doi.org/10.3847/1538-4357/aaaa2b. https://www.osti.gov/servlets/purl/1542018.
@article{osti_1542018,
title = {Continuum Reverberation Mapping of the Accretion Disks in Two Seyfert 1 Galaxies},
author = {Fausnaugh, M. M. and Starkey, D. A. and Horne, Keith and Kochanek, C. S. and Peterson, B. M. and Bentz, M. C. and Denney, K. D. and Grier, C. J. and Grupe, D. and Pogge, R. W. and De Rosa, G. and Adams, S. M. and Barth, A. J. and Beatty, Thomas G. and Bhattacharjee, A. and Borman, G. A. and Boroson, T. A. and Bottorff, M. C. and Brown, Jacob E. and Brown, Jonathan S. and Brotherton, M. S. and Coker, C. T. and Crawford, S. M. and Croxall, K. V. and Eftekharzadeh, Sarah and Eracleous, Michael and Joner, M. D. and Henderson, C. B. and Holoien, T. W. -S. and Hutchison, T. and Kaspi, Shai and Kim, S. and King, Anthea L. and Li, Miao and Lochhaas, Cassandra and Ma, Zhiyuan and MacInnis, F. and Manne-Nicholas, E. R. and Mason, M. and Montuori, Carmen and Mosquera, Ana and Mudd, Dale and Musso, R. and Nazarov, S. V. and Nguyen, M. L. and Okhmat, D. N. and Onken, Christopher A. and Ou-Yang, B. and Pancoast, A. and Pei, L. and Penny, Matthew T. and Poleski, Radosław and Rafter, Stephen and Romero-Colmenero, E. and Runnoe, Jessie and Sand, David J. and Schimoia, Jaderson S. and Sergeev, S. G. and Shappee, B. J. and Simonian, Gregory V. and Somers, Garrett and Spencer, M. and Stevens, Daniel J. and Tayar, Jamie and Treu, T. and Valenti, Stefano and Van Saders, J. and Villanueva, Jr., S. and Villforth, C. and Weiss, Yaniv and Winkler, H. and Zhu, W.},
abstractNote = {We present optical continuum lags for two Seyfert 1 galaxies, MCG+08-11-011 and NGC 2617, using monitoring data from a reverberation mapping campaign carried out in 2014. Our light curves span the ugriz filters over four months, with median cadences of 1.0 and 0.6 days for MCG+08-11-011 and NGC 2617, respectively, combined with roughly daily X-ray and near-UV data from Swift for NGC 2617. We find lags consistent with geometrically thin accretion-disk models that predict a lag-wavelength relation of τ ∝ λ 4/3. However, the observed lags are larger than predictions based on standard thin-disk theory by factors of 3.3 for MCG+08-11-011 and 2.3 for NGC 2617. Furthermore, these differences can be explained if the mass accretion rates are larger than inferred from the optical luminosity by a factor of 4.3 in MCG+08-11-011 and a factor of 1.3 in NGC 2617, although uncertainty in the SMBH masses determines the significance of this result. While the X-ray variability in NGC 2617 precedes the UV/optical variability, the long (2.6 day) lag is problematic for coronal reprocessing models.},
doi = {10.3847/1538-4357/aaaa2b},
journal = {The Astrophysical Journal (Online)},
number = 2,
volume = 854,
place = {United States},
year = {Fri Feb 16 00:00:00 EST 2018},
month = {Fri Feb 16 00:00:00 EST 2018}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 30 works
Citation information provided by
Web of Science

Figures / Tables:

Table 1 Table 1: Physical Parameters

Note. Columns 2, 3, and 4 are taken from Fausnaugh et al. (2017). Column 3 was derived from continuum-Hβ lags, and includes all systematic uncertainties. Column 4 is calculated from the observed mean optical luminosity, assuming a bolometric correction of 10 ($L = 10\lambda{L}_{5100 Å}$).more » Note that this value has been corrected for Galactic extinction and host-galaxy starlight. Columns 6 was calculated assuming a radiative efficiency of $η$ = 0.1 (see Section 2 and Equation (3)).« less

Save / Share:

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
  • DOI: 10.1088/0067-0049/182/2/543

Slim accretion disks
journal, September 1988

  • Abramowicz, M. A.; Czerny, B.; Lasota, J. P.
  • The Astrophysical Journal, Vol. 332
  • DOI: 10.1086/166683

A Method for Optimal Image Subtraction
journal, August 1998

  • Alard, C.; Lupton, Robert H.
  • The Astrophysical Journal, Vol. 503, Issue 1
  • DOI: 10.1086/305984

Correlated X-ray/optical variability in the quasar MR 2251−178
journal, September 2008


Correlation and time delays of the X-ray and optical emission of the Seyfert Galaxy NGC 3783
journal, August 2009


Astropy: A community Python package for astronomy
journal, September 2013


Instability, turbulence, and enhanced transport in accretion disks
journal, January 1998


Accretion disk Dynamo as the Trigger for X-Ray Binary State Transitions
journal, August 2015

  • Begelman, Mitchell C.; Armitage, Philip J.; Reynolds, Christopher S.
  • The Astrophysical Journal, Vol. 809, Issue 2
  • DOI: 10.1088/0004-637X/809/2/118

Magnetically elevated accretion discs in active galactic nuclei: broad emission-line regions and associated star formation
journal, October 2016

  • Begelman, Mitchell C.; Silk, Joseph
  • Monthly Notices of the Royal Astronomical Society, Vol. 464, Issue 2
  • DOI: 10.1093/mnras/stw2533

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
  • DOI: 10.1088/0004-637X/729/1/34

General Overview of Black Hole Accretion Theory
journal, May 2013


Reverberation mapping of the emission line regions of Seyfert galaxies and quasars
journal, April 1982

  • Blandford, R. D.; McKee, C. F.
  • The Astrophysical Journal, Vol. 255
  • DOI: 10.1086/159843

Long-term optical and X-ray variability of the Seyfert galaxy Markarian 79
journal, March 2009


Twelve years of X-ray and optical variability in the Seyfert galaxy NGC 4051: X-ray/optical variability in NGC 4051
journal, February 2010


The Centurion 18 telescope of the Wise Observatory
journal, February 2008

  • Brosch, Noah; Polishook, David; Shporer, Avi
  • Astrophysics and Space Science, Vol. 314, Issue 1-3
  • DOI: 10.1007/s10509-008-9752-4

Las Cumbres Observatory Global Telescope Network
journal, September 2013

  • Brown, T. M.; Baliber, N.; Bianco, F. B.
  • Publications of the Astronomical Society of the Pacific, Vol. 125, Issue 931
  • DOI: 10.1086/673168

Ultraviolet and X-ray variability of active galactic nuclei with Swift
journal, September 2016

  • Buisson, D. J. K.; Lohfink, A. M.; Alston, W. N.
  • Monthly Notices of the Royal Astronomical Society, Vol. 464, Issue 3
  • DOI: 10.1093/mnras/stw2486

Quasi-Stellar Objects
journal, September 1967


The Swift X-Ray Telescope
journal, October 2005


Testing thermal reprocessing in active galactic nuclei accretion discs
journal, August 2007


Active galactic nuclei at z ∼ 1.5 – I. Spectral energy distribution and accretion discs
journal, December 2014

  • Capellupo, D. M.; Netzer, H.; Lira, P.
  • Monthly Notices of the Royal Astronomical Society, Vol. 446, Issue 4
  • DOI: 10.1093/mnras/stu2266

The emission lines of quasars and similar objects
journal, October 1979


Swift Monitoring of NGC 4151: Evidence for a Second X-Ray/UV Reprocessing
journal, May 2017


SPACE TELESCOPE AND OPTICAL REVERBERATION MAPPING PROJECT. II. SWIFT AND HST REVERBERATION MAPPING OF THE ACCRETION DISK OF NGC 5548
journal, June 2015


Atlas of quasar energy distributions
journal, November 1994

  • Elvis, Martin; Wilkes, Belinda J.; McDowell, Jonathan C.
  • The Astrophysical Journal Supplement Series, Vol. 95
  • DOI: 10.1086/192093

A New Approach to the Internal Calibration of Reverberation-Mapping Spectra
journal, January 2017


Space Telescope and Optical Reverberation Mapping Project. iii. Optical Continuum Emission and Broadband time Delays in ngc 5548
journal, April 2016


Reverberation Mapping of Optical Emission Lines in Five Active Galaxies
journal, May 2017

  • Fausnaugh, M. M.; Grier, C. J.; Bentz, M. C.
  • The Astrophysical Journal, Vol. 840, Issue 2
  • DOI: 10.3847/1538-4357/aa6d52

The origin of the UV/optical lags in NGC 5548
journal, April 2017

  • Gardner, Emma; Done, Chris
  • Monthly Notices of the Royal Astronomical Society, Vol. 470, Issue 3
  • DOI: 10.1093/mnras/stx946

The accuracy of cross-correlation estimates of quasar emission-line region sizes
journal, September 1987

  • Gaskell, C. Martin; Peterson, Bradley M.
  • The Astrophysical Journal Supplement Series, Vol. 65
  • DOI: 10.1086/191216

Direct probe of the inner accretion flow around the supermassive black hole in NGC 2617
journal, January 2017


Long-term monitoring of Ark 120 with Swift
journal, October 2016

  • Gliozzi, M.; Papadakis, I. E.; Grupe, D.
  • Monthly Notices of the Royal Astronomical Society, Vol. 464, Issue 4
  • DOI: 10.1093/mnras/stw2636

Interpreting broad emission-line variations – I. Factors influencing the emission-line response
journal, August 2014

  • Goad, M. R.; Korista, K. T.
  • Monthly Notices of the Royal Astronomical Society, Vol. 444, Issue 1
  • DOI: 10.1093/mnras/stu1456

A two-phase model for the X-ray emission from Seyfert galaxies
journal, October 1991

  • Haardt, F.; Maraschi, L.
  • The Astrophysical Journal, Vol. 380
  • DOI: 10.1086/186171

Matplotlib: A 2D Graphics Environment
journal, January 2007


Detection of Time Lags between Quasar Continuum Emission Bands Based On Pan-STARRS Light Curves
journal, February 2017

  • Jiang (姜燕飞), Yan-Fei; Green, Paul J.; Greene, Jenny E.
  • The Astrophysical Journal, Vol. 836, Issue 2
  • DOI: 10.3847/1538-4357/aa5b91

Radiation Magnetohydrodynamic Simulations of the Formation of hot Accretion disk Coronae
journal, March 2014


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
  • DOI: 10.1088/0004-637X/783/1/47

The characteristic blue spectra of accretion disks in quasars as uncovered in the infrared
journal, July 2008

  • Kishimoto, Makoto; Antonucci, Robert; Blaes, Omer
  • Nature, Vol. 454, Issue 7203
  • DOI: 10.1038/nature07114

The buried Balmer-edge signatures from quasars
journal, November 2004


Constraints on the temperature inhomogeneity in quasar accretion discs from the ultraviolet-optical spectral variability
journal, March 2015

  • Kokubo, Mitsuru
  • Monthly Notices of the Royal Astronomical Society, Vol. 449, Issue 1
  • DOI: 10.1093/mnras/stv241

The relationship between variable and polarized optical spectral components of luminous type 1 non-blazar quasars
journal, May 2016

  • Kokubo, Mitsuru
  • Publications of the Astronomical Society of Japan, Vol. 68, Issue 4
  • DOI: 10.1093/pasj/psw050

The Variable Diffuse Continuum Emission of Broad‐Line Clouds
journal, June 2001

  • Korista, Kirk T.; Goad, Michael R.
  • The Astrophysical Journal, Vol. 553, Issue 2
  • DOI: 10.1086/320964

Limitations on the recovery of the true AGN variability parameters using damped random walk modeling
journal, January 2017


Ultraviolet variability of NGC 5548 - Dynamics of the continuum production region and geometry of the broad-line region
journal, April 1991

  • Krolik, J. H.; Horne, Keith; Kallman, T. R.
  • The Astrophysical Journal, Vol. 371
  • DOI: 10.1086/169918

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
  • DOI: 10.1088/0004-637X/800/2/144

Long-term monitoring of the archetype Seyfert galaxy MCG-6-30-15: X-ray, optical and near-IR variability of the corona, disc and torus
journal, September 2015

  • Lira, P.; Arévalo, P.; Uttley, P.
  • Monthly Notices of the Royal Astronomical Society, Vol. 454, Issue 1
  • DOI: 10.1093/mnras/stv1945

Transonic Black Hole Accretion Disks: A Unified Model for Optically Thin and Thick Disks
journal, May 1998

  • Luo, C.; Liang, E. P.
  • The Astrophysical Journal, Vol. 498, Issue 1
  • DOI: 10.1086/305555

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
  • DOI: 10.1093/mnras/stv2997

X-Ray versus Optical Variations in the Seyfert 1 Nucleus NGC 3516: A Puzzling Disconnectedness
journal, October 2002

  • Maoz, Dan; Markowitz, Alex; Edelson, Rick
  • The Astronomical Journal, Vol. 124, Issue 4
  • DOI: 10.1086/342937

Correlated X‐Ray and Optical Variability in Markarian 509
journal, April 2008

  • Marshall, Kevin; Ryle, Wesley T.; Miller, H. Richard
  • The Astrophysical Journal, Vol. 677, Issue 2
  • DOI: 10.1086/525845

Swift monitoring of NGC 5548: X-ray reprocessing and short-term UV/optical variability
journal, August 2014

  • McHardy, I. M.; Cameron, D. T.; Dwelly, T.
  • Monthly Notices of the Royal Astronomical Society, Vol. 444, Issue 2
  • DOI: 10.1093/mnras/stu1636

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
  • DOI: 10.1088/0004-637X/712/2/1129

The Structure of the X-Ray and Optical Emitting Regions of the Lensed Quasar q 2237+0305
journal, May 2013


Advection-dominated Accretion: Underfed Black Holes and Neutron Stars
journal, October 1995

  • Narayan, Ramesh; Yi, Insu
  • The Astrophysical Journal, Vol. 452
  • DOI: 10.1086/176343

On the Bardeen–Petterson effect in black hole accretion discs
journal, February 2015

  • Nealon, Rebecca; Price, Daniel J.; Nixon, Chris J.
  • Monthly Notices of the Royal Astronomical Society, Vol. 448, Issue 2
  • DOI: 10.1093/mnras/stv014

AGN Dusty Tori. II. Observational Implications of Clumpiness
journal, September 2008

  • Nenkova, Maia; Sirocky, Matthew M.; Nikutta, Robert
  • The Astrophysical Journal, Vol. 685, Issue 1
  • DOI: 10.1086/590483

Radiative Efficiency and Thermal Spectrum of Accretion onto Schwarzschild Black Holes
journal, November 2011

  • Noble, Scott C.; Krolik, Julian H.; Schnittman, Jeremy D.
  • The Astrophysical Journal, Vol. 743, Issue 2
  • DOI: 10.1088/0004-637X/743/2/115

The curtain remains open: NGC 2617 continues in a high state
journal, January 2017

  • Oknyansky, V. L.; Gaskell, C. M.; Huseynov, N. A.
  • Monthly Notices of the Royal Astronomical Society
  • DOI: 10.1093/mnras/stx149

Python for Scientific Computing
journal, January 2007


Supermassive Black Holes in Active Galactic Nuclei. II. Calibration of the Black Hole Mass–Velocity Dispersion Relationship for Active Galactic Nuclei
journal, November 2004

  • Onken, Christopher A.; Ferrarese, Laura; Merritt, David
  • The Astrophysical Journal, Vol. 615, Issue 2
  • DOI: 10.1086/424655

Disk-Accretion onto a Black Hole. Time-Averaged Structure of Accretion Disk
journal, July 1974

  • Page, Don N.; Thorne, Kip S.
  • The Astrophysical Journal, Vol. 191
  • DOI: 10.1086/152990

Modelling reverberation mapping data – II. Dynamical modelling of the Lick AGN Monitoring Project 2008 data set
journal, October 2014

  • Pancoast, Anna; Brewer, Brendon J.; Treu, Tommaso
  • Monthly Notices of the Royal Astronomical Society, Vol. 445, Issue 3
  • DOI: 10.1093/mnras/stu1419

Space Telescope and Optical Reverberation Mapping Project. V. Optical Spectroscopic Campaign and Emission-line Analysis for NGC 5548
journal, March 2017


Characteristic QSO Accretion Disk Temperatures from Spectroscopic Continuum Variability
journal, May 2006

  • Pereyra, Nicolas A.; Vanden Berk, Daniel E.; Turnshek, David A.
  • The Astrophysical Journal, Vol. 642, Issue 1
  • DOI: 10.1086/500919

Reverberation mapping of active galactic nuclei
journal, March 1993

  • Peterson, Bradley M.
  • Publications of the Astronomical Society of the Pacific, Vol. 105
  • DOI: 10.1086/133140

Measuring the Masses of Supermassive Black Holes
journal, May 2013


Central Masses and Broad‐Line Region Sizes of Active Galactic Nuclei. II. A Homogeneous Analysis of a Large Reverberation‐Mapping Database
journal, October 2004

  • Peterson, B. M.; Ferrarese, L.; Gilbert, K. M.
  • The Astrophysical Journal, Vol. 613, Issue 2
  • DOI: 10.1086/423269

Black Hole Models for Active Galactic Nuclei
journal, September 1984


On the size and Location of the X-Ray Emitting Coronae Around Black Holes
journal, May 2013


Fluorescent iron lines as a probe of astrophysical black hole systems
journal, April 2003


The Swift Ultra-Violet/Optical Telescope
journal, October 2005

  • Roming, Peter W. A.; Kennedy, Thomas E.; Mason, Keith O.
  • Space Science Reviews, Vol. 120, Issue 3-4
  • DOI: 10.1007/s11214-005-5095-4

Updating quasar bolometric luminosity corrections: Updating quasar bolometric corrections
journal, February 2012

  • Runnoe, Jessie C.; Brotherton, Michael S.; Shang, Zhaohui
  • Monthly Notices of the Royal Astronomical Society, Vol. 422, Issue 1
  • DOI: 10.1111/j.1365-2966.2012.20620.x

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
  • DOI: 10.1093/mnras/stv2385

Thin accretion discs are stabilized by a strong magnetic field
journal, April 2016

  • Sądowski, Aleksander
  • Monthly Notices of the Royal Astronomical Society, Vol. 459, Issue 4
  • DOI: 10.1093/mnras/stw913

Photon-conserving Comptonization in simulations of accretion discs around black holes
journal, October 2015

  • Sądowski, Aleksander; Narayan, Ramesh
  • Monthly Notices of the Royal Astronomical Society, Vol. 454, Issue 3
  • DOI: 10.1093/mnras/stv2022

Numerical simulations of super-critical black hole accretion flows in general relativity
journal, January 2014

  • Sądowski, Aleksander; Narayan, Ramesh; McKinney, Jonathan C.
  • Monthly Notices of the Royal Astronomical Society, Vol. 439, Issue 1
  • DOI: 10.1093/mnras/stt2479

The Color Variability of Quasars
journal, December 2011

  • Schmidt, Kasper B.; Rix, Hans-Walter; Shields, Joseph C.
  • The Astrophysical Journal, Vol. 744, Issue 2
  • DOI: 10.1088/0004-637X/744/2/147

A Monte Carlo code for Relativistic Radiation Transport Around kerr Black Holes
journal, October 2013


X-Ray Spectra from Magnetohydrodynamic Simulations of Accreting Black Holes
journal, May 2013

  • Schnittman, Jeremy D.; Krolik, Julian H.; Noble, Scott C.
  • The Astrophysical Journal, Vol. 769, Issue 2
  • DOI: 10.1088/0004-637X/769/2/156

Disk Emission from Magnetohydrodynamic Simulations of Spinning Black Holes
journal, February 2016

  • Schnittman, Jeremy D.; Krolik, Julian H.; Noble, Scott C.
  • The Astrophysical Journal, Vol. 819, Issue 1
  • DOI: 10.3847/0004-637X/819/1/48

Lag‐Luminosity Relationship for Interband Lags between Variations in B , V , R , and I Bands in Active Galactic Nuclei
journal, March 2005

  • Sergeev, S. G.; Doroshenko, V. T.; Golubinskiy, Yu. V.
  • The Astrophysical Journal, Vol. 622, Issue 1
  • DOI: 10.1086/427820

The Optical–Uv Emissivity of Quasars: Dependence on Black hole mass and Radio Loudness
journal, February 2016

  • Shankar, Francesco; Calderone, Giorgio; Knigge, Christian
  • The Astrophysical Journal, Vol. 818, Issue 1
  • DOI: 10.3847/2041-8205/818/1/L1

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


Thermal continuum from accretion disks in quasars
journal, April 1978


Constraints on the broad line region from regularized linear inversion: velocity–delay maps for five nearby active galactic nuclei
journal, September 2015

  • Skielboe, Andreas; Pancoast, Anna; Treu, Tommaso
  • Monthly Notices of the Royal Astronomical Society, Vol. 454, Issue 1
  • DOI: 10.1093/mnras/stv1917

Space Telescope and Optical Reverberation Mapping Project.Vi. Reverberating disk Models for ngc 5548
journal, January 2017


Accretion disc time lag distributions: applying CREAM to simulated AGN light curves
journal, December 2015

  • Starkey, D. A.; Horne, Keith; Villforth, C.
  • Monthly Notices of the Royal Astronomical Society, Vol. 456, Issue 2
  • DOI: 10.1093/mnras/stv2744

Reverberation Measurements of the Inner Radius of the Dust Torus in Nearby Seyfert 1 Galaxies
journal, March 2006

  • Suganuma, Masahiro; Yoshii, Yuzuru; Kobayashi, Yukiyasu
  • The Astrophysical Journal, Vol. 639, Issue 1
  • DOI: 10.1086/499326

The Rest‐Frame Extreme‐Ultraviolet Spectral Properties of Quasi‐stellar Objects
journal, February 2002

  • Telfer, Randal C.; Zheng, Wei; Kriss, Gerard A.
  • The Astrophysical Journal, Vol. 565, Issue 2
  • DOI: 10.1086/324689

The Iraf Data Reduction And Analysis System
conference, October 1986


Correlated X-ray/ultraviolet/optical variability in NGC 6814
journal, January 2016

  • Troyer, Jon; Starkey, David; Cackett, Edward M.
  • Monthly Notices of the Royal Astronomical Society, Vol. 456, Issue 4
  • DOI: 10.1093/mnras/stv2862

Evidence for orbital motion of material close to the central black hole of Mrk 766
journal, December 2005


Correlated Long-Term Optical and X-Ray Variations in NGC 5548
journal, February 2003

  • Uttley, Philip; Edelson, Rick; McHardy, Ian M.
  • The Astrophysical Journal, Vol. 584, Issue 2
  • DOI: 10.1086/373887

Robotic Reverberation Mapping of arp 151
journal, November 2015


The NumPy Array: A Structure for Efficient Numerical Computation
journal, March 2011

  • van der Walt, Stéfan; Colbert, S. Chris; Varoquaux, Gaël
  • Computing in Science & Engineering, Vol. 13, Issue 2
  • DOI: 10.1109/MCSE.2011.37

Composite Quasar Spectra from the Sloan Digital Sky Survey
journal, August 2001

  • Vanden Berk, Daniel E.; Richards, Gordon T.; Bauer, Amanda
  • The Astronomical Journal, Vol. 122, Issue 2
  • DOI: 10.1086/321167

SPITZER SPACE TELESCOPE MEASUREMENTS OF DUST REVERBERATION LAGS IN THE SEYFERT 1 GALAXY NGC 6418
journal, March 2015


Spectral classification of emission-line galaxies
journal, February 1987

  • Veilleux, Sylvain; Osterbrock, Donald E.
  • The Astrophysical Journal Supplement Series, Vol. 63
  • DOI: 10.1086/191166

Seyfert Galaxies
journal, September 1977


On the Reliability of Cross‐Correlation Function Lag Determinations in Active Galactic Nuclei
journal, November 1999

  • Welsh, W. F.
  • Publications of the Astronomical Society of the Pacific, Vol. 111, Issue 765
  • DOI: 10.1086/316457

Comments on cross-correlation methodology in variability studies of active galactic nuclei
journal, July 1994

  • White, Russell J.; Peterson, Bradley M.
  • Publications of the Astronomical Society of the Pacific, Vol. 106
  • DOI: 10.1086/133456

Spectral Variability of Quasars in the Sloan Digital Sky Survey. I. Wavelength Dependence
journal, November 2005

  • Wilhite, Brian C.; Vanden Berk, Daniel E.; Kron, Richard G.
  • The Astrophysical Journal, Vol. 633, Issue 2
  • DOI: 10.1086/430821

Is Quasar Optical Variability a Damped Random Walk?
journal, February 2013


An Alternative Approach to Measuring Reverberation lags in Active Galactic Nuclei
journal, June 2011


The Seventh Data Release of the Sloan Digital Sky Survey
text, January 2009

  • Abazajian, Kevork N.; Adelman-McCarthy, Jennifer K.; Agüeros, Marcel Andre
  • Columbia University
  • DOI: 10.7916/d8n879qg

Seyfert Galaxies
journal, January 1982


Meridional flows in the disk around a young star
journal, October 2019


CASSPER is a semantic segmentation-based particle picking algorithm for single-particle cryo-electron microscopy
journal, February 2021


Instability, Turbulence, and Enhanced Transport in Accretion Disks
journal, January 1997


Spectral Classification of Emission-Line Galaxies
journal, November 1986

  • Osterbrock, D. E.; Veilleux, S.
  • Publications of the Astronomical Society of the Pacific, Vol. 98
  • DOI: 10.1086/131945

The seventh data release of the sloan digital sky survey
text, January 2009

  • Abazajian, K. N.; Al, Et; Adelman-McCarthy, J. K.
  • Institute of Physics Publishing
  • DOI: 10.5167/uzh-30878

Seyfert Galaxies
journal, January 1969


The Centurion 18 telescope of the Wise Observatory
text, January 2008


An Alternative Approach To Measuring Reverberation Lags in Active Galactic Nuclei
text, January 2010


The Color Variability of Quasars
text, January 2011


Is Quasar Optical Variability a Damped Random Walk?
text, January 2012


A Monte Carlo Code for Relativistic Radiation Transport Around Kerr Black Holes
text, January 2013


Las Cumbres Observatory Global Telescope Network
text, January 2013


Radiation Magneto-hydrodynamic Simulations of the Formation of Hot Accretion Disk Coronae
text, January 2014


Correlated X-ray/Ultraviolet/Optical Variability in NGC 6814
text, January 2015


Accretion Disc Time Lag Distributions: Applying CREAM to Simulated AGN Light Curves
text, January 2015


Ultraviolet and X-ray variability of active galactic nuclei with Swift
text, January 2016


Reverberation Mapping of Optical Emission Lines in Five Active Galaxies
text, January 2016


Long-term monitoring of Ark 120 with Swift
text, January 2016


The curtain remains open: NGC 2617 continues in a high state
text, January 2017


Swift monitoring of NGC 4151: Evidence for a Second X-ray/UV Reprocessing
text, January 2017


The Variable Diffuse Continuum Emission of Broad Line Clouds
text, January 2001


Characteristic QSO Accretion Disk Temperatures from Spectroscopic Continuum Variability
text, January 2005


The Swift Ultra-Violet/Optical Telescope
text, January 2005


The Swift X-ray Telescope
text, January 2005


Works referencing / citing this record:

X-ray/UV/optical variability of NGC 4593 with Swift: reprocessing of X-rays by an extended reprocessor
journal, August 2018

  • McHardy, I. M.; Connolly, S. D.; Horne, K.
  • Monthly Notices of the Royal Astronomical Society, Vol. 480, Issue 3
  • DOI: 10.1093/mnras/sty1983

Quantifying the diffuse continuum contribution of BLR Clouds to AGN Continuum Inter-band Delays
journal, August 2018

  • Lawther, D.; Goad, M. R.; Korista, K. T.
  • Monthly Notices of the Royal Astronomical Society, Vol. 481, Issue 1
  • DOI: 10.1093/mnras/sty2242

Winds can ‘blow up’ AGN accretion disc sizes
journal, October 2018

  • Sun, Mouyuan; Xue, Yongquan; Trump, Jonathan R.
  • Monthly Notices of the Royal Astronomical Society, Vol. 482, Issue 2
  • DOI: 10.1093/mnras/sty2885

Reconciling the quasar microlensing disc size problem with a wind model of active galactic nucleus
journal, November 2018

  • Li, Ya-Ping; Yuan, Feng; Dai, Xinyu
  • Monthly Notices of the Royal Astronomical Society, Vol. 483, Issue 2
  • DOI: 10.1093/mnras/sty3245

Accretion Disk Size Measurement and Time Delays in the Lensed Quasar WFI 2033–4723
journal, December 2018

  • Morgan, Christopher W.; Hyer, Gregory E.; Bonvin, Vivien
  • The Astrophysical Journal, Vol. 869, Issue 2
  • DOI: 10.3847/1538-4357/aaed3e

Quasar Accretion Disk Sizes from Continuum Reverberation Mapping in the DES Standard-star Fields
journal, January 2020

  • Yu, Zhefu; Martini, Paul; Davis, T. M.
  • The Astrophysical Journal Supplement Series, Vol. 246, Issue 1
  • DOI: 10.3847/1538-4365/ab5e7a

X-ray/UV/optical variability of NGC 4593 with Swift: Reprocessing of X-rays by an extended reprocessor
text, January 2017


Winds Can "Blow Up" AGN Accretion Disk Sizes
text, January 2018


Quantifying the Diffuse Continuum Contribution of BLR Clouds to AGN Continuum Inter-band Delays
text, January 2018