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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. 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., and Zhu, W. Fri . "Continuum Reverberation Mapping of the Accretion Disks in Two Seyfert 1 Galaxies". United States. doi: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 = {2018},
month = {2}
}

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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

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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

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

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

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