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9 results on '"J. Gelbord"'

1. Intensive Broadband Reverberation Mapping of Fairall 9 with 1.8 yr of Daily Swift Monitoring

Author

R. Edelson, B. M. Peterson, J. Gelbord, K. Horne, M. Goad, I. McHardy, S. Vaughan, and M. Vestergaard

Subjects
Active galaxies, Seyfert galaxies, Astrophysics, QB460-466
Abstract

We present 1.8 yr of near-daily Swift monitoring of the bright, strongly variable Type 1 active galactic nucleus (AGN) Fairall 9. Totaling 575 successful visits, this is the largest such campaign reported to date. Variations within the UV/optical are well correlated, with longer wavelengths lagging shorter wavelengths in the direction predicted by thin-disk/lamppost models. The correlations are improved by “detrending,” subtracting a second-order polynomial fit to the UV/optical light curves to remove long-term trends that are not of interest to this study. Extensive testing indicates detrending with higher-order polynomials removes too much intrinsic variability signal on reverberation timescales. These data provide the clearest detection to date of interband lags within the UV, indicating that neither emission from a large disk nor diffuse continuum emission from the broad-line region (BLR) can independently explain the full observed lag spectrum. The observed X-ray flux variations are poorly correlated with those in the UV/optical. Further, subdivision of the data into four ∼160 days light curves shows that the UV/optical lag spectrum is highly stable throughout the four periods, but the X-ray to UV lags are unstable, significantly changing magnitude and even direction from one period to the next. This indicates the X-ray to UV relationship is more complex than predicted by the simple reprocessing model often adopted for AGN. A “bowl” model (lamppost irradiation and blackbody reprocessing on a disk with a steep rim) fit suggests the disk thickens at a distance (∼10 lt-day) and temperature (∼8000 K) consistent with the inner edge of the BLR.

Published
2024
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4. The First Swift Intensive AGN Accretion Disk Reverberation Mapping Survey

Author

R. Edelson, J. Gelbord, E. Cackett, B. M. Peterson, Keith Horne, A. J. Barth, D. A. Starkey, M. Bentz, W. N. Brandt, M. Goad, M. Joner, K. Korista, H. Netzer, K. Page, P. Uttley, S. Vaughan, A. Breeveld, S. B. Cenko, C. Done, P. Evans, M. Fausnaugh, G. Ferland, D. Gonzalez-Buitrago, J. Gropp, D. Grupe, J. Kaastra, J. Kennea, G. Kriss, S. Mathur, M. Mehdipour, D. Mudd, J. Nousek, T. Schmidt, M. Vestergaard, and C. Villforth

Subjects
Astrophysics
Abstract

Swift intensive accretion disk reverberation mapping of four AGN yielded light curves sampled ∼200–350 times in 0.3–10 keV X-ray and six UV/optical bands. Uniform reduction and cross-correlation analysis of these data sets yields three main results: (1) The X-ray/UV correlations are much weaker than those within the UV/optical, posing severe problems for the lamp-post reprocessing model in which variations in a central X-ray corona drive and power those in the surrounding accretion disk. (2) The UV/optical interband lags are generally consistent with t μ l4 3 as predicted by the centrally illuminated thin accretion disk model. While the average interband lags are somewhat larger than predicted, these results alone are not inconsistent with the thin disk model given the large systematic uncertainties involved. (3) The one exception is the U band lags, which are on average a factor of ∼2.2 larger than predicted from the surrounding band data and fits. This excess appears to be due to diffuse continuum emission from the broad-line region (BLR). The precise mixing of disk and BLR components cannot be determined from these data alone. The lags in different AGN appear to scale with mass or luminosity. We also find that there are systematic differences between the uncertainties derived by JAVELIN versus more standard lag measurement techniques, with JAVELIN reporting smaller uncertainties by a factor of 2.5 on average. In order to be conservative only standard techniques were used in the analyses reported herein.

Published
2019
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5. The luminosity-dependent contribution from the broad line region to the wavelength-dependent lags in Mrk 110

Author

F M Vincentelli, I McHardy, J V Hernández Santisteban, E M Cackett, J Gelbord, Keith Horne, J A Miller, A Lobban, 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
High Energy Astrophysical Phenomena (astro-ph.HE), Accretion, active [Galaxies], FOS: Physical sciences, DAS, Astronomy and Astrophysics, QC Physics, Space and Planetary Science, individual: Mrk 110 [Galaxies], QB Astronomy, Astrophysics - High Energy Astrophysical Phenomena, Accretion discs, QC, QB
Abstract

We have measured the wavelength-dependent lags between the X-ray, UV and optical bands in the high accretion rate ($L/L_{\rm Edd}\approx40\%$) Active Galactic Nucleus Mrk 110 during two intensive monitoring campaigns in February and September 2019. We divide the observations into three intervals with different X-ray luminosities. The first interval, already published in Vincentelli et al. (2021), has the lowest X-ray luminosity and did not exhibit the U-band excess positive lag, or the X-ray excess negative lag that is seen in most AGN. However, these excess lags are seen in the two subsequent intervals of higher X-ray luminosity. Although the data are limited, the excess lags appear to scale with X-ray luminosity. Our modelling shows that lags expected from reprocessing of X-rays by the accretion disc vary hardly at all with increasing luminosity. Therefore, as the U-band excess almost certainly arises from Balmer continuum emission from the broad line region (BLR), we attribute these lag changes to changes in the contribution from the BLR. The change is easily explained by the usual increase in the inner radius of the BLR with increasing ionising luminosity., Comment: 6 pages, 4 figures. Accepted for publication in MNRAS Letters

Published
2022
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6. Swift monitoring of NGC 5548: X-ray reprocessing and short term UV/optical variability

Author

Ian M. McHardy, Phil Uttley, Dimitrios Emmanoulopoulos, P. Lira, Doug Cameron, Tom Dwelly, J. Gelbord, P. Arévalo, Elmé Breedt, S. Connolly, and High Energy Astrophys. & Astropart. Phys (API, FNWI)

Subjects
Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Photon, Accretion (meteorology), Astrophysics::High Energy Astrophysical Phenomena, X-ray, Astronomy, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy, Black hole, Accretion rate, Wavelength, Accretion disc, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics::Galaxy Astrophysics
Abstract

Lags measured from correlated X-ray/UV/optical monitoring of AGN allow us to determine whether UV/optical variability is driven by reprocessing of X-rays or X-ray variability is driven by UV/optical seed photon variations. We present the results of the largest study to date of the relationship between the X-ray, UV and optical variability in an AGN with 554 observations, over a 750d period, of the Seyfert 1 galaxy NGC 5548 with Swift. There is a good overall correlation between the X-ray and UV/optical bands, particularly on short timescales (tens of days). These bands lag the X-ray band with lags which are proportional to wavelength to the power 1.23+/-0.31. This power is very close to the power (4/3) expected if short timescale UV/optical variability is driven by reprocessing of X-rays by a surrounding accretion disc. The observed lags, however, are longer than expected from a standard Shakura-Sunyaev accretion disc with X-ray heating, given the currently accepted black hole mass and accretion rate values, but can be explained with a slightly larger mass and accretion rate, and a generally hotter disc. Some long term UV/optical variations are not paralleled exactly in the X-rays, suggesting an additional component to the UV/optical variability arising perhaps from accretion rate perturbations propagating inwards through the disc., 6 pages, 10 figures, accepted for publication in the Monthly Notices of the Royal Astronomical Society

Published
2014

7. Swift Follow-up Observations of Candidate Gravitational-wave Transient Events

Author

P. A. Evans, J. K. Fridriksson, N. Gehrels, J. Homan, J. P. Osborne, M. Siegel, A. Beardmore, P. Handbauer, J. Gelbord, J. A. Kennea, M. Smith, Q. Zhu, J. Aasi, J. Abadie, B. P. Abbott, R. Abbott, T. D. Abbott, M. Abernathy, T. Accadia, F. Acernese, C. Adams, T. Adams, P. Addesso, R. Adhikari, C. Affeldt, M. Agathos, K. Agatsuma, P. Ajith, B. Allen, A. Allocca, E. Amador Ceron, D. Amariutei, S. B. Anderson, W. G. Anderson, K. Arai, M. C. Araya, S. Ast, S. M. Aston, P. Astone, D. Atkinson, P. Aufmuth, C. Aulbert, B. E. Aylott, S. Babak, P. Baker, G. Ballardin, S. Ballmer, Y. Bao, J. C. B. Barayoga, D. Barker, F. Barone, B. Barr, L. Barsotti, M. Barsuglia, M. A. Barton, I. Bartos, R. Bassiri, M. Bastarrika, A. Basti, J. Batch, J. Bauchrowitz, T.h. S. Bauer, M. Bebronne, D. Beck, B. Behnke, M. Bejger, M. G. Beker, A. S. Bell, C. Bell, I. Belopolski, M. Benacquista, J. M. Berliner, A. Bertolini, J. Betzwieser, N. Beveridge, P. T. Beyersdorf, T. Bhadbade, I. A. Bilenko, G. Billingsley, J. Birch, R. Biswas, M. Bitossi, M. A. Bizouard, E. Black, J. K. Blackburn, L. Blackburn, D. Blair, B. Bland, M. Blom, O. Bock, T. P. Bodiya, C. Bogan, C. Bond, R. Bondarescu, F. Bondu, L. Bonelli, R. Bonnand, R. Bork, M. Born, V. Boschi, S. Bose, L. Bosi, B. Bouhou, S. Braccini, C. Bradaschia, P. R. Brady, V. B. Braginsky, M. Branchesi, J. E. Brau, J. Breyer, T. Briant, D. O. Bridges, A. Brillet, M. Brinkmann, V. Brisson, M. Britzger, A. F. Brooks, D. A. Brown, T. Bulik, H. J. Bulten, A. Buonanno, J. Burguet Castell, D. Buskulic, C. Buy, R. L. Byer, L. Cadonati, G. Cagnoli, J. B. Camp, P. Campsie, K. Cannon, B. Canuel, J. Cao, C. D. Capano, F. Carbognani, L. Carbone, S. Caride, S. Caudill, M. Cavaglià, F. Cavalier, R. Cavalieri, G. Cella, C. Cepeda, E. Cesarini, T. Chalermsongsak, P. Charlton, E. Chassande Mottin, W. Chen, X. Chen, Y. Chen, A. Chincarini, A. Chiummo, H. S. Cho, J. Chow, N. Christensen, S. S. Y. Chua, C. T. Y. Chung, S. Chung, G. Ciani, F. Clara, D. E. Clark, J. A. Clark, J. H. Clayton, F. Cleva, E. Coccia, P. F. Cohadon, C. N. Colacino, A. Colla, M. Colombini, A. Conte, R. Conte, D. Cook, T. R. Corbitt, M. Cordier, N. Cornish, A. Corsi, C. A. Costa, M. Coughlin, J. P. Coulon, P. Couvares, D. M. Coward, M. Cowart, D. C. Coyne, J. D. E. Creighton, T. D. Creighton, A. M. Cruise, A. Cumming, L. Cunningham, E. Cuoco, R. M. Cutler, K. Dahl, M. Damjanic, S. L. Danilishin, S. D'Antonio, K. Danzmann, V. Dattilo, B. Daudert, H. Daveloza, M. Davier, E. J. Daw, R. Day, T. Dayanga, D. DeBra, G. Debreczeni, J. Degallaix, W. Del Pozzo, T. Dent, V. Dergachev, R. DeRosa, S. Dhurandhar, L. Di Fiore, A. Di Lieto, I. Di Palma, M. Di Paolo Emilio, A. Di Virgilio, M. Díaz, A. Dietz, F. Donovan, K. L. Dooley, S. Doravari, S. Dorsher, M. Drago, R. W. P. Drever, J. C. Driggers, Z. Du, J. C. Dumas, S. Dwyer, T. Eberle, M. Edgar, M. Edwards, A. Effler, P. Ehrens, S. Eikenberry, G. Endrőczi, R. Engel, T. Etzel, K. Evans, M. Evans, T. Evans, M. Factourovich, V. Fafone, S. Fairhurst, B. F. Farr, M. Favata, D. Fazi, H. Fehrmann, D. Feldbaum, I. Ferrante, F. Ferrini, F. Fidecaro, L. S. Finn, I. Fiori, R. P. Fisher, R. Flaminio, S. Foley, E. Forsi, N. Fotopoulos, J. D. Fournier, J. Franc, S. Franco, S. Frasca, F. Frasconi, M. Frede, M. A. Frei, Z. Frei, A. Freise, R. Frey, T. T. Fricke, D. Friedrich, P. Fritschel, V. V. Frolov, M. K. Fujimoto, P. J. Fulda, M. Fyffe, J. Gair, M. Galimberti, L. Gammaitoni, J. Garcia, M. E. Gáspár, G. Gelencser, G. Gemme, E. Genin, A. Gennai, L. Á. Gergely, S. Ghosh, J. A. Giaime, S. Giampanis, K. D. Giardina, A. Giazotto, S. Gil Casanova, C. Gill, J. Gleason, E. Goetz, G. González, M. L. Gorodetsky, S. Goßler, R. Gouaty, C. Graef, P. B. Graff, M. Granata, A. Grant, C. Gray, R. J. S. Greenhalgh, A. M. Gretarsson, C. Griffo, H. Grote, K. Grover, S. Grunewald, G. M. Guidi, C. Guido, R. Gupta, E. K. Gustafson, R. Gustafson, J. M. Hallam, D. Hammer, G. Hammond, J. Hanks, C. Hanna, J. Hanson, J. Harms, G. M. Harry, I. W. Harry, E. D. Harstad, M. T. Hartman, K. Haughian, K. Hayama, J. F. Hayau, J. Heefner, A. Heidmann, M. C. Heintze, H. Heitmann, P. Hello, G. Hemming, M. A. Hendry, I. S. Heng, A. W. Heptonstall, V. Herrera, M. Heurs, M. Hewitson, S. Hild, D. Hoak, K. A. Hodge, K. Holt, M. Holtrop, T. Hong, S. Hooper, J. Hough, E. J. Howell, B. Hughey, S. Husa, S. H. Huttner, T. Huynh Dinh, D. R. Ingram, R. Inta, T. Isogai, A. Ivanov, K. Izumi, M. Jacobson, E. James, Y. J. Jang, P. Jaranowski, E. Jesse, W. W. Johnson, D. I. Jones, R. Jones, R. J. G. Jonker, L. Ju, P. Kalmus, V. Kalogera, S. Kandhasamy, G. Kang, J. B. Kanner, M. Kasprzack, R. Kasturi, E. Katsavounidis, W. Katzman, H. Kaufer, K. Kaufman, K. Kawabe, S. Kawamura, F. Kawazoe, D. Keitel, D. Kelley, W. Kells, D. G. Keppel, Z. Keresztes, A. Khalaidovski, F. Y. Khalili, E. A. Khazanov, B. K. Kim, C. Kim, H. Kim, K. Kim, N. Kim, Y. M. Kim, P. J. King, D. L. Kinzel, J. S. Kissel, S. Klimenko, J. Kline, K. Kokeyama, V. Kondrashov, S. Koranda, W. Z. Korth, I. Kowalska, D. Kozak, V. Kringel, B. Krishnan, A. Królak, G. Kuehn, P. Kumar, R. Kumar, R. Kurdyumov, P. Kwee, P. K. Lam, M. Landry, A. Langley, B. Lantz, N. Lastzka, C. Lawrie, A. Lazzarini, A. Le Roux, P. Leaci, C. H. Lee, H. K. Lee, H. M. Lee, J. R. Leong, I. Leonor, N. Leroy, N. Letendre, V. Lhuillier, J. Li, T. G. F. Li, P. E. Lindquist, V. Litvine, Y. Liu, Z. Liu, N. A. Lockerbie, D. Lodhia, J. Logue, M. Lorenzini, V. Loriette, M. Lormand, G. Losurdo, J. Lough, M. Lubinski, H. Lück, A. P. Lundgren, J. Macarthur, E. Macdonald, B. Machenschalk, M. MacInnis, D. M. Macleod, M. Mageswaran, K. Mailand, E. Majorana, I. Maksimovic, V. Malvezzi, N. Man, I. Mandel, V. Mandic, M. Mantovani, F. Marchesoni, F. Marion, S. Márka, Z. Márka, A. Markosyan, E. Maros, J. Marque, F. Martelli, I. W. Martin, R. M. Martin, J. N. Marx, K. Mason, A. Masserot, F. Matichard, L. Matone, R. A. Matzner, N. Mavalvala, G. Mazzolo, R. McCarthy, D. E. McClelland, P. McDaniel, S. C. McGuire, G. McIntyre, J. McIver, G. D. Meadors, M. Mehmet, T. Meier, A. Melatos, A. C. Melissinos, G. Mendell, D. F. Menéndez, R. A. Mercer, S. Meshkov, C. Messenger, M. S. Meyer, H. Miao, C. Michel, J. Miller, Y. Minenkov, C. M. F. Mingarelli, V. P. Mitrofanov, G. Mitselmakher, R. Mittleman, B. Moe, M. Mohan, S. R. P. Mohapatra, D. Moraru, G. Moreno, N. Morgado, A. Morgia, T. Mori, S. R. Morriss, K. Mossavi, B. Mours, C. M. Mow Lowry, C. L. Mueller, G. Mueller, S. Mukherjee, A. Mullavey, H. Müller Ebhardt, J. Munch, D. Murphy, P. G. Murray, A. Mytidis, T. Nash, L. Naticchioni, V. Necula, J. Nelson, I. Neri, G. Newton, T. Nguyen, A. Nishizawa, A. Nitz, F. Nocera, D. Nolting, M. E. Normandin, L. Nuttall, E. Ochsner, J. O'Dell, E. Oelker, G. H. Ogin, J. J. Oh, S. H. Oh, R. G. Oldenberg, B. O'Reilly, R. O'Shaughnessy, C. Osthelder, C. D. Ott, D. J. Ottaway, R. S. Ottens, H. Overmier, B. J. Owen, A. Page, L. Palladino, C. Palomba, Y. Pan, C. Pankow, F. Paoletti, R. Paoletti, M. A. Papa, A. Pasqualetti, R. Passaquieti, D. Passuello, M. Pedraza, S. Penn, A. Perreca, G. Persichetti, M. Phelps, M. Pichot, M. Pickenpack, F. Piergiovanni, V. Pierro, M. Pihlaja, L. Pinard, I. M. Pinto, M. Pitkin, H. J. Pletsch, M. V. Plissi, R. Poggiani, J. Pöld, F. Postiglione, C. Poux, M. Prato, V. Predoi, T. Prestegard, L. R. Price, M. Prijatelj, M. Principe, S. Privitera, R. Prix, G. A. Prodi, L. G. Prokhorov, O. Puncken, M. Punturo, P. Puppo, V. Quetschke, R. Quitzow James, F. J. Raab, D. S. Rabeling, I. Rácz, H. Radkins, P. Raffai, M. Rakhmanov, C. Ramet, B. Rankins, P. Rapagnani, V. Raymond, V. Re, C. M. Reed, T. Reed, T. Regimbau, S. Reid, D. H. Reitze, F. Ricci, R. Riesen, K. Riles, M. Roberts, N. A. Robertson, F. Robinet, C. Robinson, E. L. Robinson, A. Rocchi, S. Roddy, C. Rodriguez, M. Rodruck, L. Rolland, J. G. Rollins, J. D. Romano, R. Romano, J. H. Romie, D. Rosińska, C. Röver, S. Rowan, A. Rüdiger, P. Ruggi, K. Ryan, F. Salemi, L. Sammut, V. Sandberg, S. Sankar, V. Sannibale, L. Santamaría, I. Santiago Prieto, G. Santostasi, E. Saracco, B. Sassolas, B. S. Sathyaprakash, P. R. Saulson, R. L. Savage, R. Schilling, R. Schnabel, R. M. S. Schofield, B. Schulz, B. F. Schutz, P. Schwinberg, J. Scott, S. M. Scott, F. Seifert, D. Sellers, D. Sentenac, A. Sergeev, D. A. Shaddock, M. Shaltev, B. Shapiro, P. Shawhan, D. H. Shoemaker, T. L. Sidery, X. Siemens, D. Sigg, D. Simakov, A. Singer, L. Singer, A. M. Sintes, G. R. Skelton, B. J. J. Slagmolen, J. Slutsky, J. R. Smith, M. R. Smith, R. J. E. Smith, N. D. Smith Lefebvre, K. Somiya, B. Sorazu, F. C. Speirits, L. Sperandio, M. Stefszky, E. Steinert, J. Steinlechner, S. Steinlechner, S. Steplewski, A. Stochino, R. Stone, K. A. Strain, S. E. Strigin, A. S. Stroeer, R. Sturani, A. L. Stuver, T. Z. Summerscales, M. Sung, S. Susmithan, P. J. Sutton, B. Swinkels, G. Szeifert, M. Tacca, L. Taffarello, D. Talukder, D. B. Tanner, S. P. Tarabrin, R. Taylor, A. P. M. ter Braack, P. Thomas, K. A. Thorne, K. S. Thorne, E. Thrane, A. Thüring, C. Titsler, K. V. Tokmakov, C. Tomlinson, A. Toncelli, M. Tonelli, O. Torre, C. V. Torres, C. I. Torrie, E. Tournefier, F. Travasso, G. Traylor, M. Tse, D. Ugolini, H. Vahlbruch, G. Vajente, J. F. J. van den Brand, C. Van Den Broeck, S. van der Putten, A. A. van Veggel, S. Vass, M. Vasuth, R. Vaulin, M. Vavoulidis, A. Vecchio, G. Vedovato, J. Veitch, P. J. Veitch, K. Venkateswara, D. Verkindt, F. Vetrano, A. Viceré, A. E. Villar, J. Y. Vinet, S. Vitale, H. Vocca, C. Vorvick, S. P. Vyatchanin, A. Wade, L. Wade, M. Wade, S. J. Waldman, L. Wallace, Y. Wan, M. Wang, X. Wang, A. Wanner, R. L. Ward, M. Was, M. Weinert, A. J. Weinstein, R. Weiss, T. Welborn, L. Wen, P. Wessels, M. West, T. Westphal, K. Wette, J. T. Whelan, S. E. Whitcomb, D. J. White, B. F. Whiting, K. Wiesner, C. Wilkinson, P. A. Willems, L. Williams, R. Williams, B. Willke, M. Wimmer, L. Winkelmann, W. Winkler, C. C. Wipf, A. G. Wiseman, H. Wittel, G. Woan, R. Wooley, J. Worden, J. Yablon, I. Yakushin, H. Yamamoto, K. Yamamoto, C. C. Yancey, H. Yang, D. Yeaton Massey, S. Yoshida, M. Yvert, A. Zadrożny, M. Zanolin, J. P. Zendri, F. Zhang, L. Zhang, C. Zhao, N. Zotov, M. E. Zucker, J. Zweizig, PINTO, INNOCENZO, CALLONI, ENRICO, DE ROSA, ROSARIO, FORTE, LUCA ANTONIO, GARUFI, FABIO, MILANO, LEOPOLDO, MOSCA, simona, PARISI, MARIA, (Astro)-Particles Physics, Mathematical Analysis, The LIGO Scientific Collaboration, The Virgo Collaboration, Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de l'Accélérateur Linéaire (LAL), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des matériaux avancés (LMA), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon, Laboratoire d'Annecy de Physique des Particules ( LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules ), Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Université Savoie Mont Blanc ( USMB [Université de Savoie] [Université de Chambéry] ) -Centre National de la Recherche Scientifique ( CNRS ), APC - Cosmologie, Physique Corpusculaire et Cosmologie - Collège de France ( PCC ), Collège de France ( CdF ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Université Paris Diderot - Paris 7 ( UPD7 ) -Centre National de la Recherche Scientifique ( CNRS ) -Collège de France ( CdF ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Université Paris Diderot - Paris 7 ( UPD7 ) -Centre National de la Recherche Scientifique ( CNRS ) -AstroParticule et Cosmologie ( APC - UMR 7164 ), Centre National de la Recherche Scientifique ( CNRS ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Observatoire de Paris-Université Paris Diderot - Paris 7 ( UPD7 ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Centre National de la Recherche Scientifique ( CNRS ) -Observatoire de Paris-Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), Laboratoire de l'Accélérateur Linéaire ( LAL ), Université Paris-Sud - Paris 11 ( UP11 ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ), Institut de Physique de Rennes ( IPR ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire des matériaux avancés ( LMA ), Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), AstroParticule et Cosmologie ( APC - UMR 7164 ), Centre National de la Recherche Scientifique ( CNRS ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Observatoire de Paris-Université Paris Diderot - Paris 7 ( UPD7 ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), APC - Gravitation ( APC-Gravitation ), Centre National de la Recherche Scientifique ( CNRS ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Observatoire de Paris-Université Paris Diderot - Paris 7 ( UPD7 ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Centre National de la Recherche Scientifique ( CNRS ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Observatoire de Paris-Université Paris Diderot - Paris 7 ( UPD7 ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut), Max-Planck-Institut-Max-Planck-Institut, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Physique Corpusculaire et Cosmologie - Collège de France (PCC), Collège de France (CdF)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Collège de France (CdF)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), APC - Gravitation (APC-Gravitation), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Evans, P. A., Fridriksson, J. K., Gehrels, N., Homan, J., Osborne, J. P., Siegel, M., Beardmore, A., Handbauer, P., Gelbord, J., Kennea, J. A., Smith, M., Zhu, Q., Aasi, J., Abadie, J., Abbott, B. P., Abbott, R., Abbott, T. D., Abernathy, M., Accadia, T., Acernese, F., Adams, C., Adams, T., Addesso, P., Adhikari, R., Affeldt, C., Agathos, M., Agatsuma, K., Ajith, P., Allen, B., Allocca, A., Amador Ceron, E., Amariutei, D., Anderson, S. B., Anderson, W. G., Arai, K., Araya, M. C., Ast, S., Aston, S. M., Astone, P., Atkinson, D., Aufmuth, P., Aulbert, C., Aylott, B. E., Babak, S., Baker, P., Ballardin, G., Ballmer, S., Bao, Y., Barayoga, J. C. B., Barker, D., Barone, F., Barr, B., Barsotti, L., Barsuglia, M., Barton, M. A., Bartos, I., Bassiri, R., Bastarrika, M., Basti, A., Batch, J., Bauchrowitz, J., Bauer, T. h. S., Bebronne, M., Beck, D., Behnke, B., Bejger, M., Beker, M. G., Bell, A. S., Bell, C., Belopolski, I., Benacquista, M., Berliner, J. M., Bertolini, A., Betzwieser, J., Beveridge, N., Beyersdorf, P. T., Bhadbade, T., Bilenko, I. A., Billingsley, G., Birch, J., Biswas, R., Bitossi, M., Bizouard, M. A., Black, E., Blackburn, J. K., Blackburn, L., Blair, D., Bland, B., Blom, M., Bock, O., Bodiya, T. P., Bogan, C., Bond, C., Bondarescu, R., Bondu, F., Bonelli, L., Bonnand, R., Bork, R., Born, M., Boschi, V., Bose, S., Bosi, L., Bouhou, B., Braccini, S., Bradaschia, C., Brady, P. R., Braginsky, V. B., Branchesi, M., Brau, J. E., Breyer, J., Briant, T., Bridges, D. O., Brillet, A., Brinkmann, M., Brisson, V., Britzger, M., Brooks, A. F., Brown, D. A., Bulik, T., Bulten, H. J., Buonanno, A., Burguet Castell, J., Buskulic, D., Buy, C., Byer, R. L., Cadonati, L., Cagnoli, G., Calloni, Enrico, Camp, J. B., Campsie, P., Cannon, K., Canuel, B., Cao, J., Capano, C. D., Carbognani, F., Carbone, L., Caride, S., Caudill, S., Cavaglià, M., Cavalier, F., Cavalieri, R., Cella, G., Cepeda, C., Cesarini, E., Chalermsongsak, T., Charlton, P., Chassande Mottin, E., Chen, W., Chen, X., Chen, Y., Chincarini, A., Chiummo, A., Cho, H. S., Chow, J., Christensen, N., Chua, S. S. Y., Chung, C. T. Y., Chung, S., Ciani, G., Clara, F., Clark, D. E., Clark, J. A., Clayton, J. H., Cleva, F., Coccia, E., Cohadon, P. F., Colacino, C. N., Colla, A., Colombini, M., Conte, A., Conte, R., Cook, D., Corbitt, T. R., Cordier, M., Cornish, N., Corsi, A., Costa, C. A., Coughlin, M., Coulon, J. P., Couvares, P., Coward, D. M., Cowart, M., Coyne, D. C., Creighton, J. D. E., Creighton, T. D., Cruise, A. M., Cumming, A., Cunningham, L., Cuoco, E., Cutler, R. M., Dahl, K., Damjanic, M., Danilishin, S. L., D'Antonio, S., Danzmann, K., Dattilo, V., Daudert, B., Daveloza, H., Davier, M., Daw, E. J., Day, R., Dayanga, T., DE ROSA, Rosario, Debra, D., Debreczeni, G., Degallaix, J., Del Pozzo, W., Dent, T., Dergachev, V., Derosa, R., Dhurandhar, S., Di Fiore, L., Di Lieto, A., Di Palma, I., Di Paolo Emilio, M., Di Virgilio, A., Díaz, M., Dietz, A., Donovan, F., Dooley, K. L., Doravari, S., Dorsher, S., Drago, M., Drever, R. W. P., Driggers, J. C., Du, Z., Dumas, J. C., Dwyer, S., Eberle, T., Edgar, M., Edwards, M., Effler, A., Ehrens, P., Eikenberry, S., Endrőczi, G., Engel, R., Etzel, T., Evans, K., Evans, M., Evans, T., Factourovich, M., Fafone, V., Fairhurst, S., Farr, B. F., Favata, M., Fazi, D., Fehrmann, H., Feldbaum, D., Ferrante, I., Ferrini, F., Fidecaro, F., Finn, L. S., Fiori, I., Fisher, R. P., Flaminio, R., Foley, S., Forsi, E., Forte, LUCA ANTONIO, Fotopoulos, N., Fournier, J. D., Franc, J., Franco, S., Frasca, S., Frasconi, F., Frede, M., Frei, M. A., Frei, Z., Freise, A., Frey, R., Fricke, T. T., Friedrich, D., Fritschel, P., Frolov, V. V., Fujimoto, M. K., Fulda, P. J., Fyffe, M., Gair, J., Galimberti, M., Gammaitoni, L., Garcia, J., Garufi, Fabio, Gáspár, M. E., Gelencser, G., Gemme, G., Genin, E., Gennai, A., Gergely, L. Á., Ghosh, S., Giaime, J. A., Giampanis, S., Giardina, K. D., Giazotto, A., Gil Casanova, S., Gill, C., Gleason, J., Goetz, E., González, G., Gorodetsky, M. L., Goßler, S., Gouaty, R., Graef, C., Graff, P. B., Granata, M., Grant, A., Gray, C., Greenhalgh, R. J. S., Gretarsson, A. M., Griffo, C., Grote, H., Grover, K., Grunewald, S., Guidi, G. M., Guido, C., Gupta, R., Gustafson, E. K., Gustafson, R., Hallam, J. M., Hammer, D., Hammond, G., Hanks, J., Hanna, C., Hanson, J., Harms, J., Harry, G. M., Harry, I. W., Harstad, E. D., Hartman, M. T., Haughian, K., Hayama, K., Hayau, J. F., Heefner, J., Heidmann, A., Heintze, M. C., Heitmann, H., Hello, P., Hemming, G., Hendry, M. A., Heng, I. S., Heptonstall, A. W., Herrera, V., Heurs, M., Hewitson, M., Hild, S., Hoak, D., Hodge, K. A., Holt, K., Holtrop, M., Hong, T., Hooper, S., Hough, J., Howell, E. J., Hughey, B., Husa, S., Huttner, S. H., Huynh Dinh, T., Ingram, D. R., Inta, R., Isogai, T., Ivanov, A., Izumi, K., Jacobson, M., James, E., Jang, Y. J., Jaranowski, P., Jesse, E., Johnson, W. W., Jones, D. I., Jones, R., Jonker, R. J. G., Ju, L., Kalmus, P., Kalogera, V., Kandhasamy, S., Kang, G., Kanner, J. B., Kasprzack, M., Kasturi, R., Katsavounidis, E., Katzman, W., Kaufer, H., Kaufman, K., Kawabe, K., Kawamura, S., Kawazoe, F., Keitel, D., Kelley, D., Kells, W., Keppel, D. G., Keresztes, Z., Khalaidovski, A., Khalili, F. Y., Khazanov, E. A., Kim, B. K., Kim, C., Kim, H., Kim, K., Kim, N., Kim, Y. M., King, P. J., Kinzel, D. L., Kissel, J. S., Klimenko, S., Kline, J., Kokeyama, K., Kondrashov, V., Koranda, S., Korth, W. Z., Kowalska, I., Kozak, D., Kringel, V., Krishnan, B., Królak, A., Kuehn, G., Kumar, P., Kumar, R., Kurdyumov, R., Kwee, P., Lam, P. K., Landry, M., Langley, A., Lantz, B., Lastzka, N., Lawrie, C., Lazzarini, A., Le Roux, A., Leaci, P., Lee, C. H., Lee, H. K., Lee, H. M., Leong, J. R., Leonor, I., Leroy, N., Letendre, N., Lhuillier, V., Li, J., T. G. F., Li, Lindquist, P. E., Litvine, V., Liu, Y., Liu, Z., Lockerbie, N. A., Lodhia, D., Logue, J., Lorenzini, M., Loriette, V., Lormand, M., Losurdo, G., Lough, J., Lubinski, M., Lück, H., Lundgren, A. P., Macarthur, J., Macdonald, E., Machenschalk, B., Macinnis, M., Macleod, D. M., Mageswaran, M., Mailand, K., Majorana, E., Maksimovic, I., Malvezzi, V., Man, N., Mandel, I., Mandic, V., Mantovani, M., Marchesoni, F., Marion, F., Márka, S., Márka, Z., Markosyan, A., Maros, E., Marque, J., Martelli, F., Martin, I. W., Martin, R. M., Marx, J. N., Mason, K., Masserot, A., Matichard, F., Matone, L., Matzner, R. A., Mavalvala, N., Mazzolo, G., Mccarthy, R., Mcclelland, D. E., Mcdaniel, P., Mcguire, S. C., Mcintyre, G., Mciver, J., Meadors, G. D., Mehmet, M., Meier, T., Melatos, A., Melissinos, A. C., Mendell, G., Menéndez, D. F., Mercer, R. A., Meshkov, S., Messenger, C., Meyer, M. S., Miao, H., Michel, C., Milano, Leopoldo, Miller, J., Minenkov, Y., Mingarelli, C. M. F., Mitrofanov, V. P., Mitselmakher, G., Mittleman, R., Moe, B., Mohan, M., Mohapatra, S. R. P., Moraru, D., Moreno, G., Morgado, N., Morgia, A., Mori, T., Morriss, S. R., Mosca, Simona, Mossavi, K., Mours, B., Mow Lowry, C. M., Mueller, C. L., Mueller, G., Mukherjee, S., Mullavey, A., Müller Ebhardt, H., Munch, J., Murphy, D., Murray, P. G., Mytidis, A., Nash, T., Naticchioni, L., Necula, V., Nelson, J., Neri, I., Newton, G., Nguyen, T., Nishizawa, A., Nitz, A., Nocera, F., Nolting, D., Normandin, M. E., Nuttall, L., Ochsner, E., O'Dell, J., Oelker, E., Ogin, G. H., J. J., Oh, S. H., Oh, Oldenberg, R. G., O'Reilly, B., O'Shaughnessy, R., Osthelder, C., Ott, C. D., Ottaway, D. J., Ottens, R. S., Overmier, H., Owen, B. 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Subjects
Swift, ELECTROMAGNETIC COUNTERPARTS, X-rays: general, 01 natural sciences, General Relativity and Quantum Cosmology, gravitational waves, ultraviolet: general, Astronomy and Astrophysics, Space and Planetary Science, CONSTANT, Observatory, 010303 astronomy & astrophysics, QC, QB, computer.programming_language, media_common, High Energy Astrophysical Phenomena (astro-ph.HE), GAMMA-RAY BURSTS, [PHYS]Physics [physics], Physics, CALIBRATION, XMM-NEWTON, HOST GALAXIES, TELESCOPE, AFTERGLOW, GRBS, PHOTOMETRY, RADIATION, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Settore FIS/01 - Fisica Sperimentale, [PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc], Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], media_common.quotation_subject, MERGERS, FOS: Physical sciences, General Relativity and Quantum Cosmology (gr-qc), [ PHYS.GRQC ] Physics [physics]/General Relativity and Quantum Cosmology [gr-qc], GAMMA-RAY BURST, Settore FIS/05 - Astronomia e Astrofisica, 0103 physical sciences, Gravitational waves, Ultraviolet: general, 010308 nuclear & particles physics, Gravitational wave, [ PHYS.ASTR.HE ] Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astronomy, LIGO, 13. Climate action, Sky, Transient (oscillation), [ SDU.ASTR.HE ] Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], EMISSION, computer
Abstract

We present the first multi-wavelength follow-up observations of two candidate gravitational-wave (GW) transient events recorded by LIGO and Virgo in their 2009-2010 science run. The events were selected with low latency by the network of GW detectors and their candidate sky locations were observed by the Swift observatory. Image transient detection was used to analyze the collected electromagnetic data, which were found to be consistent with background. Off-line analysis of the GW data alone has also established that the selected GW events show no evidence of an astrophysical origin; one of them is consistent with background and the other one was a test, part of a "blind injection challenge". With this work we demonstrate the feasibility of rapid follow-ups of GW transients and establish the sensitivity improvement joint electromagnetic and GW observations could bring. This is a first step toward an electromagnetic follow-up program in the regime of routine detections with the advanced GW instruments expected within this decade. In that regime multi-wavelength observations will play a significant role in completing the astrophysical identification of GW sources. We present the methods and results from this first combined analysis and discuss its implications in terms of sensitivity for the present and future instruments., Submitted for publication 2012 May 25, accepted 2012 October 25, published 2012 November 21, in ApJS, 203, 28 ( http://stacks.iop.org/0067-0049/203/28 ); 14 pages, 3 figures, 6 tables; LIGO-P1100038; Science summary at http://www.ligo.org/science/Publication-S6LVSwift/index.php ; Public access area to figures, tables at https://dcc.ligo.org/cgi-bin/DocDB/ShowDocument?docid=p1100038

Published
2012
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8. PERIODIC STRUCTURE IN THE MEGAPARSEC-SCALE JET OF PKS 0637–752

Author

L. E. H. Godfrey, J. E. J. Lovell, S. Burke-Spolaor, R. Ekers, G. V. Bicknell, M. Birkinshaw, D. M. Worrall, D. L. Jauncey, D. A. Schwartz, H. L. Marshall, J. Gelbord, E. S. Perlman, and M. Georganopoulos

Subjects
Physics, Angular distance, Astrophysics::High Energy Astrophysical Phenomena, Cosmic microwave background, Astronomy and Astrophysics, Quasar, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Plasma, Kinetic energy, Jet engine, law.invention, Knot (unit), Binary black hole, Space and Planetary Science, law, High Energy Physics::Experiment, Astrophysics::Galaxy Astrophysics
Abstract

We present 18 GHz Australia Telescope Compact Array imaging of the Mpc-scale quasar jet PKS 0637-752 with angular resolution ~0.58 arcseconds. We draw attention to a spectacular train of quasi-periodic knots along the inner 11 arcseconds of the jet, with average separation ~1.1 arcsec (7.6 kpc projected). We consider two classes of model to explain the periodic knots: those that involve a static pattern through which the jet plasma travels (e.g. stationary shocks); and those that involve modulation of the jet engine. Interpreting the knots as re-confinement shocks implies the jet kinetic power Q ~ 10^{46} erg/s, but the constant knot separation along the jet is not expected in a realistic external density profile. For models involving modulation of the jet engine, we find that the required modulation period is 2 x 10^3 yr < \tau < 3 x 10^5 yr. The lower end of this range is applicable if the jet remains highly relativistic on kpc-scales, as implied by the IC/CMB model of jet X-ray emission. We suggest that the quasi-periodic jet structure in PKS 0637-752 may be analogous to the quasi-periodic jet modulation seen in the microquasar GRS 1915+105, believed to result from limit cycle behaviour in an unstable accretion disk. If variations in the accretion rate are driven by a binary black hole, the predicted orbital radius is 0.7 < a < 30 pc, which corresponds to a maximum angular separation of ~0.1 - 5 mas.

Published
2012
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9. Swift Monitoring of NGC 4151: Evidence for a Second X-Ray/UV Reprocessing.

Author

R. Edelson, J. Gelbord, E. Cackett, S. Connolly, C. Done, M. Fausnaugh, E. Gardner, N. Gehrels, M. Goad, K. Horne, I. McHardy, B. M. Peterson, S. Vaughan, M. Vestergaard, A. Breeveld, A. J. Barth, M. Bentz, M. Bottorff, W. N. Brandt, and S. M. Crawford

Subjects
*STELLAR corona, *SPIRAL galaxies, *X-rays, *LIGHT curves, *ULTRAVIOLET radiation, *ACCRETION disks
Abstract

Swift monitoring of NGC 4151 with an ∼6 hr sampling over a total of 69 days in early 2016 is used to construct light curves covering five bands in the X-rays (0.3–50 keV) and six in the ultraviolet (UV)/optical (1900–5500 Å). The three hardest X-ray bands (>2.5 keV) are all strongly correlated with no measurable interband lag, while the two softer bands show lower variability and weaker correlations. The UV/optical bands are significantly correlated with the X-rays, lagging ∼3–4 days behind the hard X-rays. The variability within the UV/optical bands is also strongly correlated, with the UV appearing to lead the optical by ∼0.5–1 days. This combination of ≳3 day lags between the X-rays and UV and ≲1 day lags within the UV/optical appears to rule out the “lamp-post” reprocessing model in which a hot, X-ray emitting corona directly illuminates the accretion disk, which then reprocesses the energy in the UV/optical. Instead, these results appear consistent with the Gardner & Done picture in which two separate reprocessings occur: first, emission from the corona illuminates an extreme-UV-emitting toroidal component that shields the disk from the corona; this then heats the extreme-UV component, which illuminates the disk and drives its variability. [ABSTRACT FROM AUTHOR]

Published
2017
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