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1. Space Telescope and Optical Reverberation Mapping Project. IX. Velocity–Delay Maps for Broad Emission Lines in NGC 5548

Author

B. J. Shappee, J. M. Gelbord, Alessandro Siviero, Marianne Vestergaard, M. Spencer, G. A. Borman, Kevin V. Croxall, Michael Fausnaugh, Rick Edelson, M. C. Bottorff, Yair Krongold, Jeremy Jones, A. Skielboe, Nicolas Tejos, T. Hutchison, F. MacInnis, J. E. Brown, Catherine J. Grier, Hyun-Il Sung, M. L. Nguyen, Ryan Norris, Alis J. Deason, Haojing Yan, Susanna Bisogni, D. M. Crenshaw, J. A. Kennea, Alexei V. Filippenko, P. Ochner, S. V. Nazarov, A. A. Breeveld, Keith Horne, I. M. McHardy, Y. Weiss, E. Holmbeck, Wei Zhu, Michael T. Carini, J. A. Nousek, Hagai Netzer, A. Bigley, S. Hicks, Michael D. Joner, Kirk T. Korista, S. A. Klimanov, S. C. Kim, G. De Rosa, Jon C. Mauerhan, E. R. Manne-Nicholas, J. van Saders, Isaac Shivvers, Aaron J. Barth, Christopher S. Kochanek, Vardha N. Bennert, Ying Zu, Sang Chul Kim, Kelly D. Denney, Scott M. Adams, S. G. Sergeev, L. Gonzalez, F. Müller Sánchez, H. Yuk, Steven Villanueva, N. Gehrels, J. J. Jensen, R. McGurk, M. Im, Miao Li, K. Flatland, Garrett Somers, Jamie Tayar, D. Mudd, S. Geier, Enrico Maria Corsini, Phil Uttley, S. Rafter, M. Eracleous, H. W. Rix, Lorenzo Morelli, Douglas C. Leonard, Kelsey I. Clubb, Laura Vican, K. Schnülle, Smita Mathur, C. S. Turner, J. R. Parks, J.-U. Pott, M. Dietrich, Patrick L. Kelly, Jenny E. Greene, Carolin Villforth, P. Arévalo, Calen B. Henderson, Michael S. Brotherton, A. Gupta, M. W. Lau, Julia M. Comerford, Chris Done, Minjin Kim, Ori D. Fox, Gerard A. Kriss, Gary J. Ferland, Daniel Proga, S. Young, N. V. Efimova, Thomas W.-S. Holoien, P. A. Evans, Radosław Poleski, M. R. Goad, Dirk Grupe, B. Scott, Alessandro Pizzella, Zhiyuan Ma, J. S. Schimoia, J. C. Lee, Jong-Hak Woo, P. Lira, Cassandra Lochhaas, Jessie C. Runnoe, M. H. Siegel, Justin Ely, Patrick B. Hall, I. E. Papadakis, C. A. Johnson, Tommaso Treu, Emma Gardner, Todd Boroson, D. A. Starkey, Daniel J. Stevens, Thomas G. Beatty, Andrew J. King, Jelle Kaastra, Edward M. Cackett, Misty C. Bentz, J. S. Brown, Liuyi Pei, D. N. Okhmat, Steve Croft, M. A. Malkan, G. V. Simonian, M. Dehghanian, C. Montuori, Bradley M. Peterson, E. Dalla Bontà, R. W. Pogge, Matthew T. Penny, V. Gorjian, W. N. Brandt, Elinor L. Gates, Shai Kaspi, D. A. Saylor, Ana M. Mosquera, A. Pancoast, WeiKang Zheng, A. de Lorenzo-Cáceres, Gabriela Canalizo, ITA, USA, GBR, Science & Technology Facilities Council, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
Seyfert [Galaxies], Active galactic nucleus, active [Galaxies], 010504 meteorology & atmospheric sciences, individual (NGC 5548) [Galaxies], Active galaxies, Astrophysical black holes, Supermassive black holes, Active galactic nuclei, Reverberation mapping, astro-ph.GA, T-NDAS, FOS: Physical sciences, Astrophysics, Astronomy & Astrophysics, 01 natural sciences, Atomic, Physical Chemistry, Virial theorem, Reverberation mapping, Particle and Plasma Physics, Spitzer Space Telescope, Supermassive black holes, 0103 physical sciences, QB Astronomy, Nuclear, Emission spectrum, 010303 astronomy & astrophysics, QC, QB, 0105 earth and related environmental sciences, Line (formation), Physics, Active galactic nuclei, Supermassive black hole, Astrophysical black holes, Molecular, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Black hole, QC Physics, Space and Planetary Science, nuclei [Galaxies], Astrophysics of Galaxies (astro-ph.GA), Active galaxies, Astronomical and Space Sciences, Physical Chemistry (incl. Structural)
Abstract

We report velocity-delay maps for prominent broad emission lines, Ly_alpha, CIV, HeII and H_beta, in the spectrum of NGC5548. The emission-line responses inhabit the interior of a virial envelope. The velocity-delay maps reveal stratified ionization structure. The HeII response inside 5-10 light-days has a broad single-peaked velocity profile. The Ly_alpha, CIV, and H_beta responses peak inside 10 light-days, extend outside 20 light-days, and exhibit a velocity profile with two peaks separated by 5000 km/s in the 10 to 20 light-day delay range. The velocity-delay maps show that the M-shaped lag vs velocity structure found in previous cross-correlation analysis is the signature of a Keplerian disk with a well-defined outer edge at R=20 light-days. The outer wings of the M arise from the virial envelope, and the U-shaped interior of the M is the lower half of an ellipse in the velocity-delay plane. The far-side response is weaker than that from the near side, so that we see clearly the lower half, but only faintly the upper half, of the velocity--delay ellipse. The delay tau=(R/c)(1-sin(i))=5 light-days at line center is from the near edge of the inclined ring, giving the inclination i=45 deg. A black hole mass of M=7x10^7 Msun is consistent with the velocity-delay structure. A barber-pole pattern with stripes moving from red to blue across the CIV and possibly Ly_alpha line profiles suggests the presence of azimuthal structure rotating around the far side of the broad-line region and may be the signature of precession or orbital motion of structures in the inner disk. Further HST observations of NGC 5548 over a multi-year timespan but with a cadence of perhaps 10 days rather than 1 day could help to clarify the nature of this new AGN phenomenon., 19 pages, 9 figures, ApJ in press

Published
2021

2. Space Telescope and Optical Reverberation Mapping Project. XII: Broad-line Region Modeling of NGC 5548

Author

Christopher S. Kochanek, T. Hutchison, H. W. Rix, Gary J. Ferland, Alessandro Pizzella, E. Holmbeck, E. R. Manne-Nicholas, Ori D. Fox, Radosław Poleski, I. E. Papadakis, Erin Kara, S. Young, Vardha N. Bennert, Kelly D. Denney, Daniel J. Stevens, M. Dietrich, Calen B. Henderson, WeiKang Zheng, Haojing Yan, Aaron J. Barth, P. Lira, M. C. Bottorff, Steve Croft, Jelle Kaastra, Jamie Tayar, Misty C. Bentz, Zhiyuan Ma, Laura Vican, Jenny E. Greene, J. S. Brown, M. W. Lau, F. Müller-Sánchez, Alexei V. Filippenko, Dirk Grupe, Daniel Proga, R. McGurk, Alis J. Deason, I. M. McHardy, K. Flatland, Matthew A. Malkan, Michael D. Joner, Douglas C. Leonard, Kelsey I. Clubb, Missagh Mehdipour, B. J. Shappee, Kevin V. Croxall, J. M. Gelbord, M. H. Siegel, Jon C. Mauerhan, Ying Zu, Patrick L. Kelly, Christian Knigge, Myungshin Im, Peter R. Williams, C. A. Johnson, S. V. Nazarov, J. A. Nousek, Miao Li, C. S. Turner, Andrew J. King, Marianne Vestergaard, S. C. Kim, G. De Rosa, J. R. Parks, M. Spencer, S. G. Sergeev, Steven Villanueva, Matthew T. Penny, Lorenzo Morelli, Jong-Hak Woo, D. Mudd, D. M. Crenshaw, J.-U. Pott, T. W. S. Holoien, A. A. Breeveld, D. N. Okhmat, Scott M. Adams, Carolin Villforth, Sang Chul Kim, V. Gorjian, W. N. Brandt, G. V. Simonian, Elinor L. Gates, Shai Kaspi, M. Dehghanian, D. A. Saylor, Hyun-Il Sung, Simon Vaughan, Isaac Shivvers, F. MacInnis, Minjin Kim, Edward M. Cackett, Liuyi Pei, Alessandro Siviero, Cassandra Lochhaas, Patrick B. Hall, Wei Zhu, Tommaso Treu, Thomas G. Beatty, Tim Waters, B. Scott, J. C. Lee, Jeremy Jones, M. L. Nguyen, Ryan Norris, Susanna Bisogni, Justin Ely, Keith Horne, A. Gupta, L. Gonzalez, J. J. Jensen, P. Arévalo, N. Gehrels, Catherine J. Grier, S. Geier, Enrico Maria Corsini, S. E. Rafter, P. Ochner, Y. Weiss, A. Skielboe, Michael T. Carini, Michael S. Brotherton, H. Yuk, Chris Done, Gerard A. Kriss, C. Montuori, Bradley M. Peterson, E. Dalla Bontà, Emma Gardner, D. A. Starkey, R. W. Pogge, Smita Mathur, J. A. Kennea, P. A. Evans, A. Bigley, Jessie C. Runnoe, S. Hicks, S. A. Klimanov, Todd Boroson, J. van Saders, J. S. Schimoia, Garrett Somers, Phil Uttley, Nahum Arav, G. A. Borman, J. E. Brown, Nicolas Tejos, Julia M. Comerford, A. de Lorenzo-Cáceres, Gabriela Canalizo, Ana M. Mosquera, A. Pancoast, Michael Fausnaugh, Rick Edelson, N. V. Efimova, Brendon J. Brewer, Yair Krongold, High Energy Astrophys. & Astropart. Phys (API, FNWI), University of St Andrews. School of Physics and Astronomy, University of St Andrews. St Andrews Centre for Exoplanet Science, ITA, USA, and GBR

Subjects
010504 meteorology & atmospheric sciences, Active galaxies, Active galactic nuclei, Reverberation mapping, Seyfert galaxies, Astrophysics, 01 natural sciences, Atomic, Particle and Plasma Physics, Reverberation mapping, Spitzer Space Telescope, Emission spectrum, 010303 astronomy & astrophysics, QC, Physics, Seyfert galaxies, Balmer series, 3rd-DAS, VARIABILITY, Reverbation mapping, AGN MONITORING PROJECT, symbols, STEPS, Astronomical and Space Sciences, Physical Chemistry (incl. Structural), Active galactic nucleus, astro-ph.GA, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astronomy & Astrophysics, Electromagnetic radiation, symbols.namesake, SUPERMASSIVE BLACK-HOLES, 0103 physical sciences, Nuclear, MASSES, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Active galactic nuclei, Molecular, Astronomy and Astrophysics, Light curve, Astrophysics - Astrophysics of Galaxies, Black hole, CONTINUUM, SIZE, QC Physics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Active galaxies, EMISSION
Abstract

We present geometric and dynamical modeling of the broad line region for the multi-wavelength reverberation mapping campaign focused on NGC 5548 in 2014. The dataset includes photometric and spectroscopic monitoring in the optical and ultraviolet, covering the H$\beta$, C IV, and Ly$\alpha$ broad emission lines. We find an extended disk-like H$\beta$ BLR with a mixture of near-circular and outflowing gas trajectories, while the C IV and Ly$\alpha$ BLRs are much less extended and resemble shell-like structures. There is clear radial structure in the BLR, with C IV and Ly$\alpha$ emission arising at smaller radii than the H$\beta$ emission. Using the three lines, we make three independent black hole mass measurements, all of which are consistent. Combining these results gives a joint inference of $\log_{10}(M_{\rm BH}/M_\odot) = 7.64^{+0.21}_{-0.18}$. We examine the effect of using the $V$ band instead of the UV continuum light curve on the results and find a size difference that is consistent with the measured UV-optical time lag, but the other structural and kinematic parameters remain unchanged, suggesting that the $V$ band is a suitable proxy for the ionizing continuum when exploring the BLR structure and kinematics. Finally, we compare the H$\beta$ results to similar models of data obtained in 2008 when the AGN was at a lower luminosity state. We find that the size of the emitting region increased during this time period, but the geometry and black hole mass remain unchanged, which confirms that the BLR kinematics suitably gauge the gravitational field of the central black hole., Comment: 26 pages, 19 figures, 1 table, accepted for publication in ApJ

Published
2020
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3. Space Telescope and Optical Reverberation Mapping Project. VIII. Time Variability of Emission and Absorption in NGC 5548 Based on Modeling the Ultraviolet Spectrum

Author

Andrew J. King, K. G. Teems, Gabriele Ponti, J. S. Schimoia, Calen B. Henderson, Michael S. Brotherton, S. Paltani, Nahum Arav, Alessandro Siviero, Radosław Poleski, P. Lira, Sang Chul Kim, Thomas W.-S. Holoien, Wei Zhu, A. de Lorenzo-Cáceres, M. C. Bottorff, Dirk Grupe, Gabriela Canalizo, M. Eracleous, S. G. Sergeev, F. MacInnis, Massimo Cappi, M. Dietrich, Alis J. Deason, Haojing Yan, Giorgio Matt, Ciro Pinto, Michael T. Carini, Minjin Kim, Brandon C. Kelly, I. M. McHardy, Scott M. Adams, L. Gonzalez, J. J. Jensen, Julia M. Comerford, Yair Krongold, Tim Waters, B. Scott, C. S. Turner, G. A. Borman, R. McGurk, Nicolas Tejos, J. R. Parks, K. Flatland, Michael D. Joner, Kirk T. Korista, L. Di Gesu, Emma Gardner, Jon C. Mauerhan, Jessie C. Runnoe, Douglas C. Leonard, Kelsey I. Clubb, M. H. Siegel, C. A. Johnson, D. A. Starkey, H. Yuk, M. A. Malkan, Justin Ely, Ying Zu, Aaron J. Barth, Cassandra Lochhaas, Patrick L. Kelly, E. Holmbeck, Hyun-Il Sung, Patrick B. Hall, C. Montuori, Christopher S. Kochanek, Bradley M. Peterson, Tommaso Treu, Missagh Mehdipour, Marie Wingyee Lau, A. Skielboe, Catherine J. Grier, J. A. Kennea, Thomas G. Beatty, R. W. Pogge, J. van Saders, A. Bigley, S. Hicks, Catia Silva, H. W. Rix, Vardha N. Bennert, D. M. Crenshaw, E. Dalla Bontà, Miao Li, A. A. Breeveld, Dom Walton, D. N. Okhmat, Elisa Costantini, P. Ochner, Y. Weiss, M. L. Nguyen, Ryan Norris, Susanna Bisogni, Ehud Behar, Jacobo Ebrero, Garrett Somers, Phil Uttley, S. Rafter, Kelly D. Denney, K. Schnülle, Carolin Villforth, Keith Horne, Smita Mathur, G. V. Simonian, R. Boissay-Malaquin, Gary J. Ferland, J. S. Brown, Jelle Kaastra, Ana M. Mosquera, Stefano Bianchi, Misty C. Bentz, A. Pancoast, Alessandro Pizzella, WeiKang Zheng, N. Gehrels, Daniel J. Stevens, M. Dehghanian, Kevin V. Croxall, Isaac Shivvers, A. Gupta, Chris Done, J. E. Brown, B. De Marco, Gerard A. Kriss, Steve Croft, S. V. Nazarov, J. A. Nousek, Jae-Ok Lee, P. Arévalo, G. De Rosa, Michael Fausnaugh, Rick Edelson, Phil Evans, Lorenzo Morelli, S. Geier, Enrico Maria Corsini, M. R. Goad, V. Gorjian, W. N. Brandt, Elinor L. Gates, Shai Kaspi, D. A. Saylor, Jong-Hak Woo, Edward M. Cackett, Liuyi Pei, T. Hutchison, Jamie Tayar, E. R. Manne-Nicholas, Laura Vican, Daniel Proga, Steven Villanueva, D. Mudd, J.-U. Pott, F. Müller-Sánchez, Alexei V. Filippenko, Hagai Netzer, S. A. Klimanov, B. J. Shappee, J. M. Gelbord, Marianne Vestergaard, M. Spencer, Zhiyuan Ma, Carl T. Coker, S. Y. Kim, Myungshin Im, Science & Technology Facilities Council, University of St Andrews. School of Physics and Astronomy, University of St Andrews. St Andrews Centre for Exoplanet Science, High Energy Astrophys. & Astropart. Phys (API, FNWI), Kriss, G. A., De Rosa, G., Ely, J., Peterson, B. M., Kaastra, J., Mehdipour, M., Ferland, G. J., Dehghanian, M., Mathur, S., Edelson, R., Korista, K. T., Arav, N., Barth, A. J., Bentz, M. C., Brandt, W. N., Crenshaw, D. M., Bontà, E. Dalla, Denney, K. D., Done, C., Eracleous, M., Fausnaugh, M. M., Gardner, E., Goad, M. R., Grier, C. J., Horne, Keith, Kochanek, C. S., Mchardy, I. M., Netzer, H., Pancoast, A., Pei, L., Pogge, R. W., Proga, D., Silva, C., Tejos, N., Vestergaard, M., Adams, S. M., Anderson, M. D., Arévalo, P., Beatty, T G., Behar, E., Bennert, V. N., Bianchi, S., Bigley, A., Bisogni, S., Boissay-Malaquin, R., Borman, G. A., Bottorff, M. C., Breeveld, A. A., Brotherton, M., Brown, J. E., Brown, J. S., Cackett, E. M., Canalizo, G., Cappi, M., Carini, M. T., Clubb, K. I., Comerford, J. M., Coker, C. T., Corsini, E. M., Costantini, E., Croft, S., Croxall, K. V., Deason, A. J., De Lorenzo-Cáceres, A., De Marco, B., Dietrich, M., Di Gesu, L., Ebrero, J., Evans, P. A., Filippenko, A. V., Flatland, K., Gates, E. L., Gehrels, N., Geier, S., Gelbord, J. M., Gonzalez, L., Gorjian, V., Grupe, D., Gupta, A., Hall, P. B., Henderson, C. B., Hicks, S., Holmbeck, E., Holoien, T. W. -S., Hutchison, T. A., Im, M., Jensen, J. J., Johnson, C. A., Joner, M. D., Kaspi, S., Kelly, B. C., Kelly, P. L., Kennea, J. A., Kim, M., Kim, S. C., Kim, S. Y., King, A., Klimanov, S. A., Krongold, Y., Lau, M. W., Lee, J. C., Leonard, D. C., Li, Miao, Lira, P., Lochhaas, C., Ma, Zhiyuan, Macinnis, F., Malkan, M. A., Manne-Nicholas, E. R., Matt, G., Mauerhan, J. C., Mcgurk, R., Montuori, C., Morelli, L., Mosquera, A., Mudd, D., Müller-Sánchez, F., Nazarov, S. V., Norris, R. P., Nousek, J. A., Nguyen, M. L., Ochner, P., Okhmat, D. N., Paltani, S., Parks, J. R., Pinto, C., Pizzella, A., Poleski, R., Ponti, G., Pott, J. -U., Rafter, S. E., Rix, H. -W., Runnoe, J., Saylor, D. A., Schimoia, J. S., Schnülle, K., Scott, B., Sergeev, S. G., Shappee, B. J., Shivvers, I., Siegel, M., Simonian, G. V., Siviero, A., Skielboe, A., Somers, G., Spencer, M., Starkey, D., Stevens, D. J., Sung, H. -I., Tayar, J., Teems, K. G., Treu, T., Turner, C. S., Uttley, P., Van Saders, J ., Vican, L., Villforth, C., Villanueva Jr., S., Walton, D. J., Waters, T., Weiss, Y., Woo, J. -H., Yan, H., Yuk, H., Zheng, W., Zhu, W., Zu, Y., and USA

Subjects
Seyfert [Galaxies], galaxies: active, galaxies: individual (NGC 5548), galaxies: nuclei, galaxies: Seyfert, 010504 meteorology & atmospheric sciences, Absorption spectroscopy, active [Galaxies], individual (NGC 5548) [Galaxies], Astrophysics::High Energy Astrophysical Phenomena, Continuum (design consultancy), FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Spectral line, Luminosity, 0103 physical sciences, QB Astronomy, Emission spectrum, Absorption (electromagnetic radiation), 010303 astronomy & astrophysics, QC, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, QB, Physics, Astronomy and Astrophysics, DAS, Astrophysics - Astrophysics of Galaxies, Galaxy, QC Physics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), nuclei [Galaxies], Reverberation mapping
Abstract

We model the ultraviolet spectra of the Seyfert 1 galaxy NGC~5548 obtained with the Hubble Space Telescope during the 6-month reverberation-mapping campaign in 2014. Our model of the emission from NGC 5548 corrects for overlying absorption and deblends the individual emission lines. Using the modeled spectra, we measure the response to continuum variations for the deblended and absorption-corrected individual broad emission lines, the velocity-dependent profiles of Ly$\alpha$ and C IV, and the narrow and broad intrinsic absorption features. We find that the time lags for the corrected emission lines are comparable to those for the original data. The velocity-binned lag profiles of Ly$\alpha$ and C IV have a double-peaked structure indicative of a truncated Keplerian disk. The narrow absorption lines show delayed response to continuum variations corresponding to recombination in gas with a density of $\sim 10^5~\rm cm^{-3}$. The high-ionization narrow absorption lines decorrelate from continuum variations during the same period as the broad emission lines. Analyzing the response of these absorption lines during this period shows that the ionizing flux is diminished in strength relative to the far-ultraviolet continuum. The broad absorption lines associated with the X-ray obscurer decrease in strength during this same time interval. The appearance of X-ray obscuration in $\sim\,2012$ corresponds with an increase in the luminosity of NGC 5548 following an extended low state. We suggest that the obscurer is a disk wind triggered by the brightening of NGC 5548 following the decrease in size of the broad-line region during the preceding low-luminosity state., Comment: 50 pages, 30 figures, uses aastex62.cls. Accepted for publication in ApJ, 07/06/2019. High-level products page in MAST will go live after 7/15/2019. Replaced Figure 4 on 7/12/2019 to be more red/green color-blind friendly

Published
2019
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4. Space telescope and optical reverberation mapping project. III. Optical continuum emission and broadband time delays in NGC 5548

Author

M. M. Fausnaugh, K. D. Denney, A. J. Barth, M. C. Bentz, M. C. Bottorff, M. T. Carini, K. V. Croxall, G. De Rosa, M. R. Goad, Keith Horne, M. D. Joner, S. Kaspi, M. Kim, S. A. Klimanov, C. S. Kochanek, D. C. Leonard, H. Netzer, B. M. Peterson, K. Schnülle, S. G. Sergeev, M. Vestergaard, W.-K. Zheng, Y. Zu, M. D. Anderson, P. Arévalo, C. Bazhaw, G. A. Borman, T. A. Boroson, W. N. Brandt, A. A. Breeveld, B. J. Brewer, E. M. Cackett, D. M. Crenshaw, E. Dalla Bontà, A. De Lorenzo-Cáceres, M. Dietrich, R. Edelson, N. V. Efimova, J. Ely, P. A. Evans, A. V. Filippenko, K. Flatland, N. Gehrels, S. Geier, J. M. Gelbord, L. Gonzalez, V. Gorjian, C. J. Grier, D. Grupe, P. B. Hall, S. Hicks, D. Horenstein, T. Hutchison, M. Im, J. J. Jensen, J. Jones, J. Kaastra, B. C. Kelly, J. A. Kennea, S. C. Kim, K. T. Korista, G. A. Kriss, J. C. Lee, P. Lira, F. MacInnis, E. R. Manne-Nicholas, S. Mathur, I. M. McHardy, C. Montouri, R. Musso, S. V. Nazarov, R. P. Norris, J. A. Nousek, D. N. Okhmat, A. Pancoast, I. Papadakis, J. R. Parks, L. Pei, R. W. Pogge, J.-U. Pott, S. E. Rafter, H.-W. Rix, D. A. Saylor, J. S. Schimoia, M. Siegel, M. Spencer, D. Starkey, H.-I. Sung, K. G. Teems, T. Treu, C. S. Turner, P. Uttley, C. Villforth, Y. Weiss, J.-H. Woo, H. Yan, S. Young, Science & Technology Facilities Council, University of St Andrews. School of Physics and Astronomy, and High Energy Astrophys. & Astropart. Phys (API, FNWI)

Subjects
Seyfert Supporting [Galaxies], Seyfert [Galaxies], galaxies: active, galaxies: individual (NGC 5548), galaxies: nuclei, galaxies: Seyfert, active [Galaxies], individual (NGC 5548) [Galaxies], Astrophysics::High Energy Astrophysical Phenomena, NDAS, FOS: Physical sciences, machine-readable tables [Material], Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, symbols.namesake, Spitzer Space Telescope, 0103 physical sciences, QB Astronomy, Astrophysics::Solar and Stellar Astrophysics, Emission spectrum, 010303 astronomy & astrophysics, QC, Astrophysics::Galaxy Astrophysics, active, galaxies: individual: NGC 5548, galaxies: nuclei, galaxies: Seyfert [galaxies], QB, Galáxia NGC 5548, Physics, 010308 nuclear & particles physics, Balmer series, Large Binocular Telescope, Astronomy and Astrophysics, Light curve, Astrophysics - Astrophysics of Galaxies, Galaxias seyfert, Galáxias ativas, Wavelength, QC Physics, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), nuclei [Galaxies], Eddington luminosity, symbols, Reverberation mapping, BDC, Nucleo galatico
Abstract

We present ground-based optical photometric monitoring data for NGC 5548, part of an extended multi-wavelength reverberation mapping campaign. The light curves have nearly daily cadence from 2014 January to July in nine filters (\emph{BVRI} and \emph{ugriz}). Combined with ultraviolet data from the \emph{Hubble Space Telescope} and \emph{Swift}, we confirm significant time delays between the continuum bands as a function of wavelength, extending the wavelength coverage from 1158\,\AA\ to the $z$ band ($\sim\!9160$\,\AA). We find that the lags at wavelengths longer than the {\it V} band are equal to or greater than the lags of high-ionization-state emission lines (such as He\,{\sc ii}\,$\lambda 1640$ and $\lambda 4686$), suggesting that the continuum-emitting source is of a physical size comparable to the inner broad-line region (BLR). The trend of lag with wavelength is broadly consistent with the prediction for continuum reprocessing by an accretion disk with $\tau \propto \lambda^{4/3}$. However, the lags also imply a disk radius that is 3 times larger than the prediction from standard thin-disk theory, assuming that the bolometric luminosity is 10\% of the Eddington luminosity ($L = 0.1L_{\rm Edd}$). Using optical spectra from the Large Binocular Telescope, we estimate the bias of the interband continuum lags due to BLR emission observed in the filters. We find that the bias for filters with high levels of BLR contamination ($\sim\! 20\%$) can be important for the shortest continuum lags, and likely has a significant impact on the {\it u} and {\it U} bands owing to Balmer continuum emission., Comment: 26 pages, 10 figures, accepted to ApJ. For a brief video describing the main results of this paper, please see: https://www.youtube.com/watch?v=yaYtcDvIoP0&feature=youtu.be

Published
2016
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5. DISCOVERY OF TRANSIENT INFRARED EMISSION FROM DUST HEATED BY STELLAR TIDAL DISRUPTION FLARES

Author

Alexander J. Mendez, Julian H. Krolik, S. van Velzen, and V. Gorjian

Subjects
High Energy Astrophysical Phenomena (astro-ph.HE), Physics, 010308 nuclear & particles physics, Infrared, Astrophysics::High Energy Astrophysical Phenomena, Extinction (astronomy), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Astrophysics - Astrophysics of Galaxies, 01 natural sciences, Accretion (astrophysics), Accretion disc, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Transient (oscillation), Astrophysics - High Energy Astrophysical Phenomena, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

Stars that pass within the Roche radius of a supermassive black hole will be tidally disrupted, yielding a sudden injection of gas close to the black hole horizon which produces an electromagnetic flare. A few dozen of these flares have been discovered in recent years, but current observations provide poor constraints on the bolometric luminosity and total accreted mass of these events. Using images from the Wide-field Infrared Survey Explorer (WISE), we have discovered transient 3.4 micron emission from several previously known tidal disruption flares. The observations can be explained by dust heated to its sublimation temperature due to the intense radiation of the tidal flare. From the break in the infrared light curve we infer that this hot dust is located ~0.1 pc from the supermassive black hole. Since the dust has been heated by absorbing UV and (potentially) soft X-ray photons of the flare, the reprocessing light curve yields an estimate of the bolometric flare luminosity. For the flare PTF-09ge, we infer that the most likely value of the luminosity integrated over frequencies at which dust can absorb photons is $8\times 10^{44}$ erg/s, with a factor of 3 uncertainty due to the unknown temperature of the dust. This bolometric luminosity is a factor ~10 larger than the observed black body luminosity. Our work is the first to probe dust in the nuclei of non-active galaxies on sub-parsec scales. The observed infrared luminosity implies a covering factor ~1% for the nuclear dust in the host galaxies., ApJ in press (accepted July 7, 2016)

Published
2016
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6. Broad-line reverberation in the Kepler-field Seyfert galaxy Zw 229-015

Author

T. Lowe, Jacob Rex, Jiho Lee, A. J. L. Morton, M. T. Kandrashoff, Jonelle L. Walsh, Yizhe Yang, Laura Maria Isabel Lopez, Jeffrey M. Silverman, J. Botyanszki, A. Cucciara, Peter Nugent, R. da Silva, D. Tytler, Vardha N. Bennert, Michael D. Joner, R. M. Rich, Julia M. Comerford, Carl Zeisse, Wenxiong Li, Joseph Moody, M. L. Nguyen, Jong-Hak Woo, Alessandro Sonnenfeld, David Kirkman, Eric G. Hintz, A. Pancoast, Eric Hsiao, S. B. Cenko, M. Ganeshalingam, Anna Nierenberg, Aaron J. Barth, Jieun Choi, Michele Fumagalli, C. V. Griffith, G. H. Smith, Nao Suzuki, Brian F. Gerke, M. J. Childress, C. E. Harris, M. A. Malkan, I. K. W. Kleiser, V. Gorjian, Elinor L. Gates, William C. Keel, C. D. Laney, Alexei V. Filippenko, Gaspard Duchene, Barth, A, Nguyen, M, Malkan, M, Filippenko, A, Li, W, Gorjian, V, Joner, M, Bennert, V, Botyanszki, J, Cenko, S, Childress, M, Choi, J, Comerford, J, Cucciara, A, Da Silva, R, Duchene, G, Fumagalli, M, Ganeshalingam, M, Gates, E, Gerke, B, Griffith, C, Harris, C, Hintz, E, Hsiao, E, Kandrashoff, M, Keel, W, Kirkman, D, Kleiser, I, Laney, C, Lee, J, Lopez, L, Lowe, T, Moody, J, Morton, A, Nierenberg, A, Nugent, P, Pancoast, A, Rex, J, Rich, R, Silverman, J, Smith, G, Sonnenfeld, A, Suzuki, N, Tytler, D, Walsh, J, Woo, J, Yang, Y, and Zeisse, C

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), Active galactic nucleus, 010504 meteorology & atmospheric sciences, galaxies: active, nuclei [galaxies], FOS: Physical sciences, Astrophysics, Astronomy & Astrophysics, Atomic, 01 natural sciences, law.invention, Telescope, Particle and Plasma Physics, galaxies: individual (Zw 229-015), Observatory, law, 0103 physical sciences, Nuclear, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, Solar mass, individual [galaxies], Molecular, Astronomy and Astrophysics, Light curve, Galaxy, Black hole, Space and Planetary Science, active [galaxies], astro-ph.CO, Reverberation mapping, galaxies: nuclei, Astronomical and Space Sciences, Physical Chemistry (incl. Structural), Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The Seyfert 1 galaxy Zw 229-015 is among the brightest active galaxies being monitored by the Kepler mission. In order to determine the black hole mass in Zw 229-015 from H-beta reverberation mapping, we have carried out nightly observations with the Kast Spectrograph at the Lick 3m telescope during the dark runs from June through December 2010, obtaining 54 spectroscopic observations in total. We have also obtained nightly V-band imaging with the Katzman Automatic Imaging Telescope at Lick Observatory and with the 0.9m telescope at the Brigham Young University West Mountain Observatory over the same period. We detect strong variability in the source, which exhibited more than a factor of 2 change in broad H-beta flux. From cross-correlation measurements, we find that the H-beta light curve has a rest-frame lag of 3.86(+0.69,-0.90) days with respect to the V-band continuum variations. We also measure reverberation lags for H-alpha and H-gamma and find an upper limit to the H-delta lag. Combining the H-beta lag measurement with a broad H-beta width of sigma = 1590+/-47 km/s measured from the root-mean-square variability spectrum, we obtain a virial estimate of M_BH = 1.00(-0.24,+0.19)*10^7 solar masses for the black hole in Zw 229-015. As a Kepler target, Zw 229-015 will eventually have one of the highest-quality optical light curves ever measured for any active galaxy, and the black hole mass determined from reverberation mapping will serve as a benchmark for testing relationships between black hole mass and continuum variability characteristics in active galactic nuclei., 13 pages, 8 figures. Accepted for publication in ApJ

Published
2011
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