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

Author

Horne, Keith, Horne, Keith, De Rosa, G, Peterson, BM, Barth, AJ, Ely, J, Fausnaugh, MM, Kriss, GA, Pei, L, Bentz, MC, Cackett, EM, Edelson, R, Eracleous, M, Goad, MR, Grier, CJ, Kaastra, J, Kochanek, CS, Krongold, Y, Mathur, S, Netzer, H, Proga, D, Tejos, N, Vestergaard, M, Villforth, C, Adams, SM, Anderson, MD, Arévalo, P, Beatty, TG, Bennert, VN, Bigley, A, Bisogni, S, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Brotherton, M, Brown, JE, Brown, JS, Canalizo, G, Carini, MT, Clubb, KI, Comerford, JM, Corsini, EM, Crenshaw, DM, Croft, S, Croxall, KV, Bontà, E Dalla, Deason, AJ, Dehghanian, M, De Lorenzo-Cáceres, A, Denney, KD, Dietrich, M, Done, C, Efimova, NV, Evans, PA, Ferland, GJ, Filippenko, AV, Flatland, K, Fox, OD, Gardner, E, Gates, EL, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Greene, JE, Grupe, D, Gupta, A, Hall, PB, Henderson, CB, Hicks, S, Holmbeck, E, Holoien, TW-S, Hutchison, T, Im, M, Jensen, JJ, Johnson, CA, Joner, MD, Jones, J, Kaspi, S, Kelly, PL, Kennea, JA, Kim, M, Kim, S, Kim, SC, King, A, Klimanov, SA, Korista, KT, Lau, MW, Lee, JC, Leonard, DC, Li, Miao, Lira, P, Lochhaas, C, Ma, Zhiyuan, MacInnis, F, Malkan, MA, Manne-Nicholas, ER, Mauerhan, JC, Horne, Keith, Horne, Keith, De Rosa, G, Peterson, BM, Barth, AJ, Ely, J, Fausnaugh, MM, Kriss, GA, Pei, L, Bentz, MC, Cackett, EM, Edelson, R, Eracleous, M, Goad, MR, Grier, CJ, Kaastra, J, Kochanek, CS, Krongold, Y, Mathur, S, Netzer, H, Proga, D, Tejos, N, Vestergaard, M, Villforth, C, Adams, SM, Anderson, MD, Arévalo, P, Beatty, TG, Bennert, VN, Bigley, A, Bisogni, S, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Brotherton, M, Brown, JE, Brown, JS, Canalizo, G, Carini, MT, Clubb, KI, Comerford, JM, Corsini, EM, Crenshaw, DM, Croft, S, Croxall, KV, Bontà, E Dalla, Deason, AJ, Dehghanian, M, De Lorenzo-Cáceres, A, Denney, KD, Dietrich, M, Done, C, Efimova, NV, Evans, PA, Ferland, GJ, Filippenko, AV, Flatland, K, Fox, OD, Gardner, E, Gates, EL, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Greene, JE, Grupe, D, Gupta, A, Hall, PB, Henderson, CB, Hicks, S, Holmbeck, E, Holoien, TW-S, Hutchison, T, Im, M, Jensen, JJ, Johnson, CA, Joner, MD, Jones, J, Kaspi, S, Kelly, PL, Kennea, JA, Kim, M, Kim, S, Kim, SC, King, A, Klimanov, SA, Korista, KT, Lau, MW, Lee, JC, Leonard, DC, Li, Miao, Lira, P, Lochhaas, C, Ma, Zhiyuan, MacInnis, F, Malkan, MA, Manne-Nicholas, ER, and Mauerhan, JC

Published
2021

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

Author

Williams, PR, Williams, PR, Pancoast, A, Treu, T, Brewer, BJ, Peterson, BM, Barth, AJ, Malkan, MA, De Rosa, G, Horne, Keith, Kriss, GA, Arav, N, Bentz, MC, Cackett, EM, Bontà, E Dalla, Dehghanian, M, Done, C, Ferland, GJ, Grier, CJ, Kaastra, J, Kara, E, Kochanek, CS, Mathur, S, Mehdipour, M, Pogge, RW, Proga, D, Vestergaard, M, Waters, T, Adams, SM, Anderson, MD, Arévalo, P, Beatty, TG, Bennert, VN, Bigley, A, Bisogni, S, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Brotherton, M, Brown, JE, Brown, JS, Canalizo, G, Carini, MT, Clubb, KI, Comerford, JM, Corsini, EM, Crenshaw, DM, Croft, S, Croxall, KV, Deason, AJ, De Lorenzo-Cáceres, A, Denney, KD, Dietrich, M, Edelson, R, Efimova, NV, Ely, J, Evans, PA, Fausnaugh, MM, Filippenko, AV, Flatland, K, Fox, OD, Gardner, E, Gates, EL, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Greene, JE, Grupe, D, Gupta, A, Hall, PB, Henderson, CB, Hicks, S, Holmbeck, E, Holoien, TW-S, Hutchison, T, Im, M, Jensen, JJ, Johnson, CA, Joner, MD, Jones, J, Kaspi, S, Kelly, PL, Kennea, JA, Kim, M, Kim, S, Kim, SC, King, A, Klimanov, SA, Knigge, C, Krongold, Y, Lau, MW, Lee, JC, Leonard, DC, Li, Miao, Lira, P, Lochhaas, C, Ma, Zhiyuan, Williams, PR, Williams, PR, Pancoast, A, Treu, T, Brewer, BJ, Peterson, BM, Barth, AJ, Malkan, MA, De Rosa, G, Horne, Keith, Kriss, GA, Arav, N, Bentz, MC, Cackett, EM, Bontà, E Dalla, Dehghanian, M, Done, C, Ferland, GJ, Grier, CJ, Kaastra, J, Kara, E, Kochanek, CS, Mathur, S, Mehdipour, M, Pogge, RW, Proga, D, Vestergaard, M, Waters, T, Adams, SM, Anderson, MD, Arévalo, P, Beatty, TG, Bennert, VN, Bigley, A, Bisogni, S, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Brotherton, M, Brown, JE, Brown, JS, Canalizo, G, Carini, MT, Clubb, KI, Comerford, JM, Corsini, EM, Crenshaw, DM, Croft, S, Croxall, KV, Deason, AJ, De Lorenzo-Cáceres, A, Denney, KD, Dietrich, M, Edelson, R, Efimova, NV, Ely, J, Evans, PA, Fausnaugh, MM, Filippenko, AV, Flatland, K, Fox, OD, Gardner, E, Gates, EL, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Greene, JE, Grupe, D, Gupta, A, Hall, PB, Henderson, CB, Hicks, S, Holmbeck, E, Holoien, TW-S, Hutchison, T, Im, M, Jensen, JJ, Johnson, CA, Joner, MD, Jones, J, Kaspi, S, Kelly, PL, Kennea, JA, Kim, M, Kim, S, Kim, SC, King, A, Klimanov, SA, Knigge, C, Krongold, Y, Lau, MW, Lee, JC, Leonard, DC, Li, Miao, Lira, P, Lochhaas, C, and Ma, Zhiyuan

Published
2020

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

Kriss, GA, Kriss, GA, De Rosa, G, Ely, J, Peterson, BM, Kaastra, J, Mehdipour, M, Ferland, GJ, Dehghanian, M, Mathur, S, Edelson, R, Korista, KT, Arav, N, Barth, AJ, Bentz, MC, Brandt, WN, Crenshaw, DM, Dalla Bontà, E, Denney, KD, Done, C, Eracleous, M, Fausnaugh, MM, Gardner, E, Goad, MR, Grier, CJ, Horne, K, Kochanek, CS, McHardy, IM, Netzer, H, Pancoast, A, Pei, L, Pogge, RW, Proga, D, Silva, C, Tejos, N, Vestergaard, M, Adams, SM, Anderson, MD, Arévalo, P, Beatty, TG, Behar, E, Bennert, VN, Bianchi, S, Bigley, A, Bisogni, S, Boissay-Malaquin, R, Borman, GA, Bottorff, MC, Breeveld, AA, Brotherton, M, Brown, JE, Brown, JS, Cackett, EM, Canalizo, G, Cappi, M, Carini, MT, Clubb, KI, Comerford, JM, Coker, CT, Corsini, EM, Costantini, E, Croft, S, Croxall, KV, Deason, AJ, De Lorenzo-Cáceres, A, De Marco, B, Dietrich, M, Di Gesu, L, Ebrero, J, Evans, PA, Filippenko, AV, Flatland, K, Gates, EL, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grupe, D, Gupta, A, Hall, PB, Henderson, CB, Hicks, S, Holmbeck, E, Holoien, TWS, Hutchison, TA, Im, M, Jensen, JJ, Johnson, CA, Joner, MD, Kaspi, S, Kelly, BC, Kelly, PL, Kennea, JA, Kim, M, Kim, SC, Kim, SY, King, A, Klimanov, SA, Krongold, Y, Lau, MW, Kriss, GA, Kriss, GA, De Rosa, G, Ely, J, Peterson, BM, Kaastra, J, Mehdipour, M, Ferland, GJ, Dehghanian, M, Mathur, S, Edelson, R, Korista, KT, Arav, N, Barth, AJ, Bentz, MC, Brandt, WN, Crenshaw, DM, Dalla Bontà, E, Denney, KD, Done, C, Eracleous, M, Fausnaugh, MM, Gardner, E, Goad, MR, Grier, CJ, Horne, K, Kochanek, CS, McHardy, IM, Netzer, H, Pancoast, A, Pei, L, Pogge, RW, Proga, D, Silva, C, Tejos, N, Vestergaard, M, Adams, SM, Anderson, MD, Arévalo, P, Beatty, TG, Behar, E, Bennert, VN, Bianchi, S, Bigley, A, Bisogni, S, Boissay-Malaquin, R, Borman, GA, Bottorff, MC, Breeveld, AA, Brotherton, M, Brown, JE, Brown, JS, Cackett, EM, Canalizo, G, Cappi, M, Carini, MT, Clubb, KI, Comerford, JM, Coker, CT, Corsini, EM, Costantini, E, Croft, S, Croxall, KV, Deason, AJ, De Lorenzo-Cáceres, A, De Marco, B, Dietrich, M, Di Gesu, L, Ebrero, J, Evans, PA, Filippenko, AV, Flatland, K, Gates, EL, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grupe, D, Gupta, A, Hall, PB, Henderson, CB, Hicks, S, Holmbeck, E, Holoien, TWS, Hutchison, TA, Im, M, Jensen, JJ, Johnson, CA, Joner, MD, Kaspi, S, Kelly, BC, Kelly, PL, Kennea, JA, Kim, M, Kim, SC, Kim, SY, King, A, Klimanov, SA, Krongold, Y, and Lau, MW

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 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 and C iv have a double-peaked structure indicative of a truncated Keplerian disk. The narrow absorption lines show a delayed response to continuum variations corresponding to recombination in gas with a density of ∼105 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 ∼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.

Published
2019

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

Author

Kriss, GA, Kriss, GA, De Rosa, G, Ely, J, Peterson, BM, Kaastra, J, Mehdipour, M, Ferland, GJ, Dehghanian, M, Mathur, S, Edelson, R, Korista, KT, Arav, N, Barth, AJ, Bentz, MC, Brandt, WN, Crenshaw, DM, Dalla Bontà, E, Denney, KD, Done, C, Eracleous, M, Fausnaugh, MM, Gardner, E, Goad, MR, Grier, CJ, Horne, K, Kochanek, CS, McHardy, IM, Netzer, H, Pancoast, A, Pei, L, Pogge, RW, Proga, D, Silva, C, Tejos, N, Vestergaard, M, Adams, SM, Anderson, MD, Arévalo, P, Beatty, TG, Behar, E, Bennert, VN, Bianchi, S, Bigley, A, Bisogni, S, Boissay-Malaquin, R, Borman, GA, Bottorff, MC, Breeveld, AA, Brotherton, M, Brown, JE, Brown, JS, Cackett, EM, Canalizo, G, Cappi, M, Carini, MT, Clubb, KI, Comerford, JM, Coker, CT, Corsini, EM, Costantini, E, Croft, S, Croxall, KV, Deason, AJ, De Lorenzo-Cáceres, A, De Marco, B, Dietrich, M, Di Gesu, L, Ebrero, J, Evans, PA, Filippenko, AV, Flatland, K, Gates, EL, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grupe, D, Gupta, A, Hall, PB, Henderson, CB, Hicks, S, Holmbeck, E, Holoien, TWS, Hutchison, TA, Im, M, Jensen, JJ, Johnson, CA, Joner, MD, Kaspi, S, Kelly, BC, Kelly, PL, Kennea, JA, Kim, M, Kim, SC, Kim, SY, King, A, Klimanov, SA, Krongold, Y, Lau, MW, Kriss, GA, Kriss, GA, De Rosa, G, Ely, J, Peterson, BM, Kaastra, J, Mehdipour, M, Ferland, GJ, Dehghanian, M, Mathur, S, Edelson, R, Korista, KT, Arav, N, Barth, AJ, Bentz, MC, Brandt, WN, Crenshaw, DM, Dalla Bontà, E, Denney, KD, Done, C, Eracleous, M, Fausnaugh, MM, Gardner, E, Goad, MR, Grier, CJ, Horne, K, Kochanek, CS, McHardy, IM, Netzer, H, Pancoast, A, Pei, L, Pogge, RW, Proga, D, Silva, C, Tejos, N, Vestergaard, M, Adams, SM, Anderson, MD, Arévalo, P, Beatty, TG, Behar, E, Bennert, VN, Bianchi, S, Bigley, A, Bisogni, S, Boissay-Malaquin, R, Borman, GA, Bottorff, MC, Breeveld, AA, Brotherton, M, Brown, JE, Brown, JS, Cackett, EM, Canalizo, G, Cappi, M, Carini, MT, Clubb, KI, Comerford, JM, Coker, CT, Corsini, EM, Costantini, E, Croft, S, Croxall, KV, Deason, AJ, De Lorenzo-Cáceres, A, De Marco, B, Dietrich, M, Di Gesu, L, Ebrero, J, Evans, PA, Filippenko, AV, Flatland, K, Gates, EL, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grupe, D, Gupta, A, Hall, PB, Henderson, CB, Hicks, S, Holmbeck, E, Holoien, TWS, Hutchison, TA, Im, M, Jensen, JJ, Johnson, CA, Joner, MD, Kaspi, S, Kelly, BC, Kelly, PL, Kennea, JA, Kim, M, Kim, SC, Kim, SY, King, A, Klimanov, SA, Krongold, Y, and Lau, MW

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 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 and C iv have a double-peaked structure indicative of a truncated Keplerian disk. The narrow absorption lines show a delayed response to continuum variations corresponding to recombination in gas with a density of ∼105 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 ∼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.

Published
2019

5. Space Telescope and Optical Reverberation Mapping Project. V. Optical Spectroscopic Campaign and Emission-line Analysis for NGC 5548

Author

Pei, L, Pei, L, Fausnaugh, MM, Barth, AJ, Peterson, BM, Bentz, MC, De Rosa, G, Denney, KD, Goad, MR, Kochanek, CS, Korista, KT, Kriss, GA, Pogge, RW, Bennert, VN, Brotherton, M, Clubb, KI, Bontà, E Dalla, Filippenko, AV, Greene, JE, Grier, CJ, Vestergaard, M, Zheng, W, Adams, Scott M, Beatty, Thomas G, Bigley, A, Brown, Jacob E, Brown, Jonathan S, Canalizo, G, Comerford, JM, Coker, Carl T, Corsini, EM, Croft, S, Croxall, KV, Deason, AJ, Eracleous, Michael, Fox, OD, Gates, EL, Henderson, CB, Holmbeck, E, Holoien, TW-S, Jensen, JJ, Johnson, CA, Kelly, PL, Kim, S, King, A, Lau, MW, Li, Miao, Lochhaas, Cassandra, Ma, Zhiyuan, Manne-Nicholas, ER, Mauerhan, JC, Malkan, MA, McGurk, R, Morelli, L, Mosquera, Ana, Mudd, Dale, Sanchez, F Muller, Nguyen, ML, Ochner, P, Ou-Yang, B, Pancoast, A, Penny, Matthew T, Pizzella, A, Poleski, Radosław, Runnoe, Jessie, Scott, B, Schimoia, Jaderson S, Shappee, BJ, Shivvers, I, Simonian, Gregory V, Siviero, A, Somers, Garrett, Stevens, Daniel J, Strauss, MA, Tayar, Jamie, Tejos, N, Treu, T, Van Saders, J, Vican, L, Villanueva, S, Yuk, H, Zakamska, NL, Zhu, W, Anderson, MD, Arévalo, P, Bazhaw, C, Bisogni, S, Borman, GA, Bottorff, MC, Brandt, WN, Breeveld, AA, Cackett, EM, Carini, MT, Crenshaw, DM, De Lorenzo-Cáceres, A, Dietrich, M, Edelson, R, Efimova, NV, Ely, J, Evans, PA, Ferland, GJ, Pei, L, Pei, L, Fausnaugh, MM, Barth, AJ, Peterson, BM, Bentz, MC, De Rosa, G, Denney, KD, Goad, MR, Kochanek, CS, Korista, KT, Kriss, GA, Pogge, RW, Bennert, VN, Brotherton, M, Clubb, KI, Bontà, E Dalla, Filippenko, AV, Greene, JE, Grier, CJ, Vestergaard, M, Zheng, W, Adams, Scott M, Beatty, Thomas G, Bigley, A, Brown, Jacob E, Brown, Jonathan S, Canalizo, G, Comerford, JM, Coker, Carl T, Corsini, EM, Croft, S, Croxall, KV, Deason, AJ, Eracleous, Michael, Fox, OD, Gates, EL, Henderson, CB, Holmbeck, E, Holoien, TW-S, Jensen, JJ, Johnson, CA, Kelly, PL, Kim, S, King, A, Lau, MW, Li, Miao, Lochhaas, Cassandra, Ma, Zhiyuan, Manne-Nicholas, ER, Mauerhan, JC, Malkan, MA, McGurk, R, Morelli, L, Mosquera, Ana, Mudd, Dale, Sanchez, F Muller, Nguyen, ML, Ochner, P, Ou-Yang, B, Pancoast, A, Penny, Matthew T, Pizzella, A, Poleski, Radosław, Runnoe, Jessie, Scott, B, Schimoia, Jaderson S, Shappee, BJ, Shivvers, I, Simonian, Gregory V, Siviero, A, Somers, Garrett, Stevens, Daniel J, Strauss, MA, Tayar, Jamie, Tejos, N, Treu, T, Van Saders, J, Vican, L, Villanueva, S, Yuk, H, Zakamska, NL, Zhu, W, Anderson, MD, Arévalo, P, Bazhaw, C, Bisogni, S, Borman, GA, Bottorff, MC, Brandt, WN, Breeveld, AA, Cackett, EM, Carini, MT, Crenshaw, DM, De Lorenzo-Cáceres, A, Dietrich, M, Edelson, R, Efimova, NV, Ely, J, Evans, PA, and Ferland, GJ

Published
2017

6. Space Telescope and Optical Reverberation Mapping Project. VII. Understanding the Ultraviolet Anomaly in NGC 5548 with X-Ray Spectroscopy

Author

Mathur, S, Mathur, S, Gupta, A, Page, K, Pogge, RW, Krongold, Y, Goad, MR, Adams, SM, Anderson, MD, Arévalo, P, Barth, AJ, Bazhaw, C, Beatty, TG, Bentz, MC, Bigley, A, Bisogni, S, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Brown, JE, Brown, JS, Cackett, EM, Canalizo, G, Carini, MT, Clubb, KI, Comerford, JM, Coker, CT, Corsini, EM, Crenshaw, DM, Croft, S, Croxall, KV, Dalla Bontà, E, Deason, AJ, Denney, KD, De Lorenzo-Cáceres, A, De Rosa, G, Dietrich, M, Edelson, R, Ely, J, Eracleous, M, Evans, PA, Fausnaugh, MM, Ferland, GJ, Filippenko, AV, Flatland, K, Fox, OD, Gates, EL, Gehrels, N, Geier, S, Gelbord, JM, Gorjian, V, Greene, JE, Grier, CJ, Grupe, D, Hall, PB, Henderson, CB, Hicks, S, Holmbeck, E, Holoien, TWS, Horenstein, D, Horne, K, Hutchison, T, Im, M, Jensen, JJ, Johnson, CA, Joner, MD, Jones, J, Kaastra, J, Kaspi, S, Kelly, BC, Kelly, PL, Kennea, JA, Kim, M, Kim, S, Kim, SC, King, A, Klimanov, SA, Kochanek, CS, Korista, KT, Kriss, GA, Lau, MW, Lee, JC, Leonard, DC, Li, M, Lira, P, Ma, Z, Macinnis, F, Manne-Nicholas, ER, Malkan, MA, Mauerhan, JC, McGurk, R, McHardy, IM, Montouri, C, Morelli, L, Mosquera, A, Mudd, D, Muller-Sanchez, F, Musso, R, Nazarov, SV, Mathur, S, Mathur, S, Gupta, A, Page, K, Pogge, RW, Krongold, Y, Goad, MR, Adams, SM, Anderson, MD, Arévalo, P, Barth, AJ, Bazhaw, C, Beatty, TG, Bentz, MC, Bigley, A, Bisogni, S, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Brown, JE, Brown, JS, Cackett, EM, Canalizo, G, Carini, MT, Clubb, KI, Comerford, JM, Coker, CT, Corsini, EM, Crenshaw, DM, Croft, S, Croxall, KV, Dalla Bontà, E, Deason, AJ, Denney, KD, De Lorenzo-Cáceres, A, De Rosa, G, Dietrich, M, Edelson, R, Ely, J, Eracleous, M, Evans, PA, Fausnaugh, MM, Ferland, GJ, Filippenko, AV, Flatland, K, Fox, OD, Gates, EL, Gehrels, N, Geier, S, Gelbord, JM, Gorjian, V, Greene, JE, Grier, CJ, Grupe, D, Hall, PB, Henderson, CB, Hicks, S, Holmbeck, E, Holoien, TWS, Horenstein, D, Horne, K, Hutchison, T, Im, M, Jensen, JJ, Johnson, CA, Joner, MD, Jones, J, Kaastra, J, Kaspi, S, Kelly, BC, Kelly, PL, Kennea, JA, Kim, M, Kim, S, Kim, SC, King, A, Klimanov, SA, Kochanek, CS, Korista, KT, Kriss, GA, Lau, MW, Lee, JC, Leonard, DC, Li, M, Lira, P, Ma, Z, Macinnis, F, Manne-Nicholas, ER, Malkan, MA, Mauerhan, JC, McGurk, R, McHardy, IM, Montouri, C, Morelli, L, Mosquera, A, Mudd, D, Muller-Sanchez, F, Musso, R, and Nazarov, SV

Abstract

During the Space Telescope and Optical Reverberation Mapping Project observations of NGC 5548, the continuum and emission-line variability became decorrelated during the second half of the six-month-long observing campaign. Here we present Swift and Chandra X-ray spectra of NGC 5548 obtained as part of the campaign. The Swift spectra show that excess flux (relative to a power-law continuum) in the soft X-ray band appears before the start of the anomalous emission-line behavior, peaks during the period of the anomaly, and then declines. This is a model-independent result suggesting that the soft excess is related to the anomaly. We divide the Swift data into on- and off-anomaly spectra to characterize the soft excess via spectral fitting. The cause of the spectral differences is likely due to a change in the intrinsic spectrum rather than to variable obscuration or partial covering. The Chandra spectra have lower signal-to-noise ratios, but are consistent with the Swift data. Our preferred model of the soft excess is emission from an optically thick, warm Comptonizing corona, the effective optical depth of which increases during the anomaly. This model simultaneously explains all three observations: the UV emission-line flux decrease, the soft-excess increase, and the emission-line anomaly.

Published
2017

7. SPACE TELESCOPE and OPTICAL REVERBERATION MAPPING PROJECT.VI. REVERBERATING DISK MODELS for NGC 5548

Author

Starkey, D, Starkey, D, Horne, K, Fausnaugh, MM, Peterson, BM, Bentz, MC, Kochanek, CS, Denney, KD, Edelson, R, Goad, MR, Rosa, GD, Anderson, MD, Arévalo, P, Barth, AJ, Bazhaw, C, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Cackett, EM, Carini, MT, Croxall, KV, Crenshaw, DM, Dalla Bontà, E, Lorenzo-Cáceres, AD, Dietrich, M, Efimova, NV, Ely, J, Evans, PA, Filippenko, AV, Flatland, K, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grier, CJ, Grupe, D, Hall, PB, Hicks, S, Horenstein, D, Hutchison, T, Im, M, Jensen, JJ, Joner, MD, Jones, J, Kaastra, J, Kaspi, S, Kelly, BC, Kennea, JA, Kim, SC, Kim, M, Klimanov, SA, Korista, KT, Kriss, GA, Lee, JC, Leonard, DC, Lira, P, Macinnis, F, Manne-Nicholas, ER, Mathur, S, McHardy, IM, Montouri, C, Musso, R, Nazarov, SV, Norris, RP, Nousek, JA, Okhmat, DN, Pancoast, A, Parks, JR, Pei, L, Pogge, RW, Pott, JU, Rafter, SE, Rix, HW, Saylor, DA, Schimoia, JS, Schnülle, K, Sergeev, SG, Siegel, MH, Spencer, M, Sung, HI, Teems, KG, Turner, CS, Uttley, P, Vestergaard, M, Villforth, C, Weiss, Y, Woo, JH, Yan, H, Young, AS, Zheng, W, Zu, Y, Starkey, D, Starkey, D, Horne, K, Fausnaugh, MM, Peterson, BM, Bentz, MC, Kochanek, CS, Denney, KD, Edelson, R, Goad, MR, Rosa, GD, Anderson, MD, Arévalo, P, Barth, AJ, Bazhaw, C, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Cackett, EM, Carini, MT, Croxall, KV, Crenshaw, DM, Dalla Bontà, E, Lorenzo-Cáceres, AD, Dietrich, M, Efimova, NV, Ely, J, Evans, PA, Filippenko, AV, Flatland, K, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grier, CJ, Grupe, D, Hall, PB, Hicks, S, Horenstein, D, Hutchison, T, Im, M, Jensen, JJ, Joner, MD, Jones, J, Kaastra, J, Kaspi, S, Kelly, BC, Kennea, JA, Kim, SC, Kim, M, Klimanov, SA, Korista, KT, Kriss, GA, Lee, JC, Leonard, DC, Lira, P, Macinnis, F, Manne-Nicholas, ER, Mathur, S, McHardy, IM, Montouri, C, Musso, R, Nazarov, SV, Norris, RP, Nousek, JA, Okhmat, DN, Pancoast, A, Parks, JR, Pei, L, Pogge, RW, Pott, JU, Rafter, SE, Rix, HW, Saylor, DA, Schimoia, JS, Schnülle, K, Sergeev, SG, Siegel, MH, Spencer, M, Sung, HI, Teems, KG, Turner, CS, Uttley, P, Vestergaard, M, Villforth, C, Weiss, Y, Woo, JH, Yan, H, Young, AS, Zheng, W, and Zu, Y

Abstract

We conduct a multiwavelength continuum variability study of the Seyfert 1 galaxy NGC 5548 to investigate the temperature structure of its accretion disk. The 19 overlapping continuum light curves (1158 A oto 9157 A o) combine simultaneous Hubble Space Telescope, Swift, and ground-based observations over a 180 day period from 2014 January to July. Light-curve variability is interpreted as the reverberation response of the accretion disk to irradiation by a central time-varying point source. Our model yields the disk inclination i = 36° ±10° temperature T1 = 44 ±6 ) × 10 3 K at 1 light day from the black hole, and a temperatureradius slope (T ∞r-a) of a = 0.99 ±0.03. We also infer the driving light curve and find that it correlates poorly with both the hard and soft X-ray light curves, suggesting that the X-rays alone may not drive the ultraviolet and optical variability over the observing period. We also decompose the light curves into bright, faint, and mean accretion-disk spectra. These spectra lie below that expected for a standard blackbody accretion disk accreting at L LEdd = 0.1.

Published
2017

8. SPACE TELESCOPE and OPTICAL REVERBERATION MAPPING PROJECT.VI. REVERBERATING DISK MODELS for NGC 5548

Author

Starkey, D, Starkey, D, Horne, K, Fausnaugh, MM, Peterson, BM, Bentz, MC, Kochanek, CS, Denney, KD, Edelson, R, Goad, MR, Rosa, GD, Anderson, MD, Arévalo, P, Barth, AJ, Bazhaw, C, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Cackett, EM, Carini, MT, Croxall, KV, Crenshaw, DM, Dalla Bontà, E, Lorenzo-Cáceres, AD, Dietrich, M, Efimova, NV, Ely, J, Evans, PA, Filippenko, AV, Flatland, K, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grier, CJ, Grupe, D, Hall, PB, Hicks, S, Horenstein, D, Hutchison, T, Im, M, Jensen, JJ, Joner, MD, Jones, J, Kaastra, J, Kaspi, S, Kelly, BC, Kennea, JA, Kim, SC, Kim, M, Klimanov, SA, Korista, KT, Kriss, GA, Lee, JC, Leonard, DC, Lira, P, Macinnis, F, Manne-Nicholas, ER, Mathur, S, McHardy, IM, Montouri, C, Musso, R, Nazarov, SV, Norris, RP, Nousek, JA, Okhmat, DN, Pancoast, A, Parks, JR, Pei, L, Pogge, RW, Pott, JU, Rafter, SE, Rix, HW, Saylor, DA, Schimoia, JS, Schnülle, K, Sergeev, SG, Siegel, MH, Spencer, M, Sung, HI, Teems, KG, Turner, CS, Uttley, P, Vestergaard, M, Villforth, C, Weiss, Y, Woo, JH, Yan, H, Young, AS, Zheng, W, Zu, Y, Starkey, D, Starkey, D, Horne, K, Fausnaugh, MM, Peterson, BM, Bentz, MC, Kochanek, CS, Denney, KD, Edelson, R, Goad, MR, Rosa, GD, Anderson, MD, Arévalo, P, Barth, AJ, Bazhaw, C, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Cackett, EM, Carini, MT, Croxall, KV, Crenshaw, DM, Dalla Bontà, E, Lorenzo-Cáceres, AD, Dietrich, M, Efimova, NV, Ely, J, Evans, PA, Filippenko, AV, Flatland, K, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grier, CJ, Grupe, D, Hall, PB, Hicks, S, Horenstein, D, Hutchison, T, Im, M, Jensen, JJ, Joner, MD, Jones, J, Kaastra, J, Kaspi, S, Kelly, BC, Kennea, JA, Kim, SC, Kim, M, Klimanov, SA, Korista, KT, Kriss, GA, Lee, JC, Leonard, DC, Lira, P, Macinnis, F, Manne-Nicholas, ER, Mathur, S, McHardy, IM, Montouri, C, Musso, R, Nazarov, SV, Norris, RP, Nousek, JA, Okhmat, DN, Pancoast, A, Parks, JR, Pei, L, Pogge, RW, Pott, JU, Rafter, SE, Rix, HW, Saylor, DA, Schimoia, JS, Schnülle, K, Sergeev, SG, Siegel, MH, Spencer, M, Sung, HI, Teems, KG, Turner, CS, Uttley, P, Vestergaard, M, Villforth, C, Weiss, Y, Woo, JH, Yan, H, Young, AS, Zheng, W, and Zu, Y

Abstract

We conduct a multiwavelength continuum variability study of the Seyfert 1 galaxy NGC 5548 to investigate the temperature structure of its accretion disk. The 19 overlapping continuum light curves (1158 A oto 9157 A o) combine simultaneous Hubble Space Telescope, Swift, and ground-based observations over a 180 day period from 2014 January to July. Light-curve variability is interpreted as the reverberation response of the accretion disk to irradiation by a central time-varying point source. Our model yields the disk inclination i = 36° ±10° temperature T1 = 44 ±6 ) × 10 3 K at 1 light day from the black hole, and a temperatureradius slope (T ∞r-a) of a = 0.99 ±0.03. We also infer the driving light curve and find that it correlates poorly with both the hard and soft X-ray light curves, suggesting that the X-rays alone may not drive the ultraviolet and optical variability over the observing period. We also decompose the light curves into bright, faint, and mean accretion-disk spectra. These spectra lie below that expected for a standard blackbody accretion disk accreting at L LEdd = 0.1.

Published
2017

9. Space Telescope and Optical Reverberation Mapping Project. VII. Understanding the Ultraviolet Anomaly in NGC 5548 with X-Ray Spectroscopy

Author

Mathur, S, Mathur, S, Gupta, A, Page, K, Pogge, RW, Krongold, Y, Goad, MR, Adams, SM, Anderson, MD, Arévalo, P, Barth, AJ, Bazhaw, C, Beatty, TG, Bentz, MC, Bigley, A, Bisogni, S, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Brown, JE, Brown, JS, Cackett, EM, Canalizo, G, Carini, MT, Clubb, KI, Comerford, JM, Coker, CT, Corsini, EM, Crenshaw, DM, Croft, S, Croxall, KV, Dalla Bontà, E, Deason, AJ, Denney, KD, De Lorenzo-Cáceres, A, De Rosa, G, Dietrich, M, Edelson, R, Ely, J, Eracleous, M, Evans, PA, Fausnaugh, MM, Ferland, GJ, Filippenko, AV, Flatland, K, Fox, OD, Gates, EL, Gehrels, N, Geier, S, Gelbord, JM, Gorjian, V, Greene, JE, Grier, CJ, Grupe, D, Hall, PB, Henderson, CB, Hicks, S, Holmbeck, E, Holoien, TWS, Horenstein, D, Horne, K, Hutchison, T, Im, M, Jensen, JJ, Johnson, CA, Joner, MD, Jones, J, Kaastra, J, Kaspi, S, Kelly, BC, Kelly, PL, Kennea, JA, Kim, M, Kim, S, Kim, SC, King, A, Klimanov, SA, Kochanek, CS, Korista, KT, Kriss, GA, Lau, MW, Lee, JC, Leonard, DC, Li, M, Lira, P, Ma, Z, Macinnis, F, Manne-Nicholas, ER, Malkan, MA, Mauerhan, JC, McGurk, R, McHardy, IM, Montouri, C, Morelli, L, Mosquera, A, Mudd, D, Muller-Sanchez, F, Musso, R, Nazarov, SV, Mathur, S, Mathur, S, Gupta, A, Page, K, Pogge, RW, Krongold, Y, Goad, MR, Adams, SM, Anderson, MD, Arévalo, P, Barth, AJ, Bazhaw, C, Beatty, TG, Bentz, MC, Bigley, A, Bisogni, S, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Brown, JE, Brown, JS, Cackett, EM, Canalizo, G, Carini, MT, Clubb, KI, Comerford, JM, Coker, CT, Corsini, EM, Crenshaw, DM, Croft, S, Croxall, KV, Dalla Bontà, E, Deason, AJ, Denney, KD, De Lorenzo-Cáceres, A, De Rosa, G, Dietrich, M, Edelson, R, Ely, J, Eracleous, M, Evans, PA, Fausnaugh, MM, Ferland, GJ, Filippenko, AV, Flatland, K, Fox, OD, Gates, EL, Gehrels, N, Geier, S, Gelbord, JM, Gorjian, V, Greene, JE, Grier, CJ, Grupe, D, Hall, PB, Henderson, CB, Hicks, S, Holmbeck, E, Holoien, TWS, Horenstein, D, Horne, K, Hutchison, T, Im, M, Jensen, JJ, Johnson, CA, Joner, MD, Jones, J, Kaastra, J, Kaspi, S, Kelly, BC, Kelly, PL, Kennea, JA, Kim, M, Kim, S, Kim, SC, King, A, Klimanov, SA, Kochanek, CS, Korista, KT, Kriss, GA, Lau, MW, Lee, JC, Leonard, DC, Li, M, Lira, P, Ma, Z, Macinnis, F, Manne-Nicholas, ER, Malkan, MA, Mauerhan, JC, McGurk, R, McHardy, IM, Montouri, C, Morelli, L, Mosquera, A, Mudd, D, Muller-Sanchez, F, Musso, R, and Nazarov, SV

Abstract

During the Space Telescope and Optical Reverberation Mapping Project observations of NGC 5548, the continuum and emission-line variability became decorrelated during the second half of the six-month-long observing campaign. Here we present Swift and Chandra X-ray spectra of NGC 5548 obtained as part of the campaign. The Swift spectra show that excess flux (relative to a power-law continuum) in the soft X-ray band appears before the start of the anomalous emission-line behavior, peaks during the period of the anomaly, and then declines. This is a model-independent result suggesting that the soft excess is related to the anomaly. We divide the Swift data into on- and off-anomaly spectra to characterize the soft excess via spectral fitting. The cause of the spectral differences is likely due to a change in the intrinsic spectrum rather than to variable obscuration or partial covering. The Chandra spectra have lower signal-to-noise ratios, but are consistent with the Swift data. Our preferred model of the soft excess is emission from an optically thick, warm Comptonizing corona, the effective optical depth of which increases during the anomaly. This model simultaneously explains all three observations: the UV emission-line flux decrease, the soft-excess increase, and the emission-line anomaly.

Published
2017

10. SPACE TELESCOPE AND OPTICAL REVERBERATION MAPPING PROJECT. III. OPTICAL CONTINUUM EMISSION AND BROADBAND TIME DELAYS IN NGC 5548

Author

Fausnaugh, MM, Fausnaugh, MM, Denney, KD, Barth, AJ, Bentz, MC, Bottorff, MC, Carini, MT, Croxall, KV, De Rosa, G, Goad, MR, Horne, Keith, Joner, MD, Kaspi, S, Kim, M, Klimanov, SA, Kochanek, CS, Leonard, DC, Netzer, H, Peterson, BM, Schnülle, K, Sergeev, SG, Vestergaard, M, Zheng, W-K, Zu, Y, Anderson, MD, Arévalo, P, Bazhaw, C, Borman, GA, Boroson, TA, Brandt, WN, Breeveld, AA, Brewer, BJ, Cackett, EM, Crenshaw, DM, Bontà, E Dalla, De Lorenzo-Cáceres, A, Dietrich, M, Edelson, R, Efimova, NV, Ely, J, Evans, PA, Filippenko, AV, Flatland, K, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grier, CJ, Grupe, D, Hall, PB, Hicks, S, Horenstein, D, Hutchison, T, Im, M, Jensen, JJ, Jones, J, Kaastra, J, Kelly, BC, Kennea, JA, Kim, SC, Korista, KT, Kriss, GA, Lee, JC, Lira, P, MacInnis, F, Manne-Nicholas, ER, Mathur, S, McHardy, IM, Montouri, C, Musso, R, Nazarov, SV, Norris, RP, Nousek, JA, Okhmat, DN, Pancoast, A, Papadakis, I, Parks, JR, Pei, L, Pogge, RW, Pott, J-U, Rafter, SE, Rix, H-W, Saylor, DA, Schimoia, JS, Siegel, M, Spencer, M, Starkey, D, Sung, H-I, Teems, KG, Treu, T, Turner, CS, Uttley, P, Villforth, C, Weiss, Y, Woo, J-H, Yan, H, Young, S, Fausnaugh, MM, Fausnaugh, MM, Denney, KD, Barth, AJ, Bentz, MC, Bottorff, MC, Carini, MT, Croxall, KV, De Rosa, G, Goad, MR, Horne, Keith, Joner, MD, Kaspi, S, Kim, M, Klimanov, SA, Kochanek, CS, Leonard, DC, Netzer, H, Peterson, BM, Schnülle, K, Sergeev, SG, Vestergaard, M, Zheng, W-K, Zu, Y, Anderson, MD, Arévalo, P, Bazhaw, C, Borman, GA, Boroson, TA, Brandt, WN, Breeveld, AA, Brewer, BJ, Cackett, EM, Crenshaw, DM, Bontà, E Dalla, De Lorenzo-Cáceres, A, Dietrich, M, Edelson, R, Efimova, NV, Ely, J, Evans, PA, Filippenko, AV, Flatland, K, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grier, CJ, Grupe, D, Hall, PB, Hicks, S, Horenstein, D, Hutchison, T, Im, M, Jensen, JJ, Jones, J, Kaastra, J, Kelly, BC, Kennea, JA, Kim, SC, Korista, KT, Kriss, GA, Lee, JC, Lira, P, MacInnis, F, Manne-Nicholas, ER, Mathur, S, McHardy, IM, Montouri, C, Musso, R, Nazarov, SV, Norris, RP, Nousek, JA, Okhmat, DN, Pancoast, A, Papadakis, I, Parks, JR, Pei, L, Pogge, RW, Pott, J-U, Rafter, SE, Rix, H-W, Saylor, DA, Schimoia, JS, Siegel, M, Spencer, M, Starkey, D, Sung, H-I, Teems, KG, Treu, T, Turner, CS, Uttley, P, Villforth, C, Weiss, Y, Woo, J-H, Yan, H, and Young, S

Published
2016

11. SPACE TELESCOPE and OPTICAL REVERBERATION MAPPING PROJECT. IV. ANOMALOUS BEHAVIOR of the BROAD ULTRAVIOLET EMISSION LINES in NGC 5548

Author

Goad, MR, Goad, MR, Korista, KT, Rosa, GD, Kriss, GA, Edelson, R, Barth, AJ, Ferland, GJ, Kochanek, CS, Netzer, H, Peterson, BM, Bentz, MC, Bisogni, S, Crenshaw, DM, Denney, KD, Ely, J, Fausnaugh, MM, Grier, CJ, Gupta, A, Horne, KD, Kaastra, J, Pancoast, A, Pei, L, Pogge, RW, Skielboe, A, Starkey, D, Vestergaard, M, Zu, Y, Anderson, MD, Arévalo, P, Bazhaw, C, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Brewer, BJ, Cackett, EM, Carini, MT, Croxall, KV, Bontá, ED, Lorenzo-Cáceres, AD, Dietrich, M, Efimova, NV, Evans, PA, Filippenko, AV, Flatland, K, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grupe, D, Hall, PB, Hicks, S, Horenstein, D, Hutchison, T, Im, M, Jensen, JJ, Joner, MD, Jones, J, Kaspi, S, Kelly, BC, Kennea, JA, Kim, M, Kim, SC, Klimanov, SA, Lee, JC, Leonard, DC, Lira, P, Macinnis, F, Manne-Nicholas, ER, Mathur, S, McHardy, IM, Montouri, C, Musso, R, Nazarov, SV, Norris, RP, Nousek, JA, Okhmat, DN, Papadakis, I, Parks, JR, Pott, JU, Rafter, SE, Rix, HW, Saylor, DA, Schimoia, JS, Schnülle, K, Sergeev, SG, Siegel, M, Spencer, M, Sung, HI, Teems, KG, Treu, T, Turner, CS, Uttley, P, Villforth, C, Weiss, Y, Woo, JH, Yan, H, Young, S, Goad, MR, Goad, MR, Korista, KT, Rosa, GD, Kriss, GA, Edelson, R, Barth, AJ, Ferland, GJ, Kochanek, CS, Netzer, H, Peterson, BM, Bentz, MC, Bisogni, S, Crenshaw, DM, Denney, KD, Ely, J, Fausnaugh, MM, Grier, CJ, Gupta, A, Horne, KD, Kaastra, J, Pancoast, A, Pei, L, Pogge, RW, Skielboe, A, Starkey, D, Vestergaard, M, Zu, Y, Anderson, MD, Arévalo, P, Bazhaw, C, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Brewer, BJ, Cackett, EM, Carini, MT, Croxall, KV, Bontá, ED, Lorenzo-Cáceres, AD, Dietrich, M, Efimova, NV, Evans, PA, Filippenko, AV, Flatland, K, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grupe, D, Hall, PB, Hicks, S, Horenstein, D, Hutchison, T, Im, M, Jensen, JJ, Joner, MD, Jones, J, Kaspi, S, Kelly, BC, Kennea, JA, Kim, M, Kim, SC, Klimanov, SA, Lee, JC, Leonard, DC, Lira, P, Macinnis, F, Manne-Nicholas, ER, Mathur, S, McHardy, IM, Montouri, C, Musso, R, Nazarov, SV, Norris, RP, Nousek, JA, Okhmat, DN, Papadakis, I, Parks, JR, Pott, JU, Rafter, SE, Rix, HW, Saylor, DA, Schimoia, JS, Schnülle, K, Sergeev, SG, Siegel, M, Spencer, M, Sung, HI, Teems, KG, Treu, T, Turner, CS, Uttley, P, Villforth, C, Weiss, Y, Woo, JH, Yan, H, and Young, S

Abstract

During an intensive Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS) UV monitoring campaign of the Seyfert 1 galaxy NGC 5548 performed from 2014 February to July, the normally highly correlated far UV continuum and broad emission line variations decorrelated for ∼60-70 days, starting ∼75 days after the first HST/COS observation. Following this anomalous state, the flux and variability of the broad emission lines returned to a more normal state. This transient behavior, characterized by significant deficits in flux and equivalent width of the strong broad UV emission lines, is the first of its kind to be unambiguously identified in an active galactic nucleus reverberation mapping campaign. The largest corresponding emission line flux deficits occurred for the high ionization, collisionally excited lines C iv and Si iv(+O iv]), and also He ii(+O iii]), while the anomaly in Lywas substantially smaller. This pattern of behavior indicates a depletion in the flux of photons with relative to those near 13.6 eV. We suggest two plausible mechanisms for the observed behavior: (i) temporary obscuration of the ionizing continuum incident upon broad line region (BLR) clouds by a moving veil of material lying between the inner accretion disk and inner (BLR), perhaps resulting from an episodic ejection of material from the disk, or (ii) a temporary change in the intrinsic ionizing continuum spectral energy distribution resulting in a deficit of ionizing photons with energies >54 eV, possibly due to a transient restructuring of the Comptonizing atmosphere above the disk. Current evidence appears to favor the latter explanation.

Published
2016

12. SPACE TELESCOPE and OPTICAL REVERBERATION MAPPING PROJECT. IV. ANOMALOUS BEHAVIOR of the BROAD ULTRAVIOLET EMISSION LINES in NGC 5548

Author

Goad, MR, Goad, MR, Korista, KT, Rosa, GD, Kriss, GA, Edelson, R, Barth, AJ, Ferland, GJ, Kochanek, CS, Netzer, H, Peterson, BM, Bentz, MC, Bisogni, S, Crenshaw, DM, Denney, KD, Ely, J, Fausnaugh, MM, Grier, CJ, Gupta, A, Horne, KD, Kaastra, J, Pancoast, A, Pei, L, Pogge, RW, Skielboe, A, Starkey, D, Vestergaard, M, Zu, Y, Anderson, MD, Arévalo, P, Bazhaw, C, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Brewer, BJ, Cackett, EM, Carini, MT, Croxall, KV, Bontá, ED, Lorenzo-Cáceres, AD, Dietrich, M, Efimova, NV, Evans, PA, Filippenko, AV, Flatland, K, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grupe, D, Hall, PB, Hicks, S, Horenstein, D, Hutchison, T, Im, M, Jensen, JJ, Joner, MD, Jones, J, Kaspi, S, Kelly, BC, Kennea, JA, Kim, M, Kim, SC, Klimanov, SA, Lee, JC, Leonard, DC, Lira, P, Macinnis, F, Manne-Nicholas, ER, Mathur, S, McHardy, IM, Montouri, C, Musso, R, Nazarov, SV, Norris, RP, Nousek, JA, Okhmat, DN, Papadakis, I, Parks, JR, Pott, JU, Rafter, SE, Rix, HW, Saylor, DA, Schimoia, JS, Schnülle, K, Sergeev, SG, Siegel, M, Spencer, M, Sung, HI, Teems, KG, Treu, T, Turner, CS, Uttley, P, Villforth, C, Weiss, Y, Woo, JH, Yan, H, Young, S, Goad, MR, Goad, MR, Korista, KT, Rosa, GD, Kriss, GA, Edelson, R, Barth, AJ, Ferland, GJ, Kochanek, CS, Netzer, H, Peterson, BM, Bentz, MC, Bisogni, S, Crenshaw, DM, Denney, KD, Ely, J, Fausnaugh, MM, Grier, CJ, Gupta, A, Horne, KD, Kaastra, J, Pancoast, A, Pei, L, Pogge, RW, Skielboe, A, Starkey, D, Vestergaard, M, Zu, Y, Anderson, MD, Arévalo, P, Bazhaw, C, Borman, GA, Boroson, TA, Bottorff, MC, Brandt, WN, Breeveld, AA, Brewer, BJ, Cackett, EM, Carini, MT, Croxall, KV, Bontá, ED, Lorenzo-Cáceres, AD, Dietrich, M, Efimova, NV, Evans, PA, Filippenko, AV, Flatland, K, Gehrels, N, Geier, S, Gelbord, JM, Gonzalez, L, Gorjian, V, Grupe, D, Hall, PB, Hicks, S, Horenstein, D, Hutchison, T, Im, M, Jensen, JJ, Joner, MD, Jones, J, Kaspi, S, Kelly, BC, Kennea, JA, Kim, M, Kim, SC, Klimanov, SA, Lee, JC, Leonard, DC, Lira, P, Macinnis, F, Manne-Nicholas, ER, Mathur, S, McHardy, IM, Montouri, C, Musso, R, Nazarov, SV, Norris, RP, Nousek, JA, Okhmat, DN, Papadakis, I, Parks, JR, Pott, JU, Rafter, SE, Rix, HW, Saylor, DA, Schimoia, JS, Schnülle, K, Sergeev, SG, Siegel, M, Spencer, M, Sung, HI, Teems, KG, Treu, T, Turner, CS, Uttley, P, Villforth, C, Weiss, Y, Woo, JH, Yan, H, and Young, S

Abstract

During an intensive Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS) UV monitoring campaign of the Seyfert 1 galaxy NGC 5548 performed from 2014 February to July, the normally highly correlated far UV continuum and broad emission line variations decorrelated for ∼60-70 days, starting ∼75 days after the first HST/COS observation. Following this anomalous state, the flux and variability of the broad emission lines returned to a more normal state. This transient behavior, characterized by significant deficits in flux and equivalent width of the strong broad UV emission lines, is the first of its kind to be unambiguously identified in an active galactic nucleus reverberation mapping campaign. The largest corresponding emission line flux deficits occurred for the high ionization, collisionally excited lines C iv and Si iv(+O iv]), and also He ii(+O iii]), while the anomaly in Lywas substantially smaller. This pattern of behavior indicates a depletion in the flux of photons with relative to those near 13.6 eV. We suggest two plausible mechanisms for the observed behavior: (i) temporary obscuration of the ionizing continuum incident upon broad line region (BLR) clouds by a moving veil of material lying between the inner accretion disk and inner (BLR), perhaps resulting from an episodic ejection of material from the disk, or (ii) a temporary change in the intrinsic ionizing continuum spectral energy distribution resulting in a deficit of ionizing photons with energies >54 eV, possibly due to a transient restructuring of the Comptonizing atmosphere above the disk. Current evidence appears to favor the latter explanation.

Published
2016

13. Space Telescope and Optical Reverberation Mapping Project. I. Ultraviolet Observations of the Seyfert 1 Galaxy NGC 5548 With the Cosmic Origins Spectrograph on Hubble Space Telescope

Author

De Rosa, G, De Rosa, G, Peterson, BM, Ely, J, Kriss, GA, Crenshaw, DM, Horne, K, Korista, KT, Netzer, H, Pogge, RW, Arévalo, P, Barth, AJ, Bentz, MC, Brandt, WN, Breeveld, AA, Brewer, BJ, Dalla Bontá, E, Lorenzo-Cáceres, AD, Denney, KD, Dietrich, M, Edelson, R, Evans, PA, Fausnaugh, MM, Gehrels, N, Gelbord, JM, Goad, MR, Grier, CJ, Grupe, D, Hall, PB, Kaastra, J, Kelly, BC, Kennea, JA, Kochanek, CS, Lira, P, Mathur, S, McHardy, IM, Nousek, JA, Pancoast, A, Papadakis, I, Pei, L, Schimoia, JS, Siegel, M, Starkey, D, Treu, T, Uttley, P, Vaughan, S, Vestergaard, M, Villforth, C, Yan, H, Young, S, Zu, Y, De Rosa, G, De Rosa, G, Peterson, BM, Ely, J, Kriss, GA, Crenshaw, DM, Horne, K, Korista, KT, Netzer, H, Pogge, RW, Arévalo, P, Barth, AJ, Bentz, MC, Brandt, WN, Breeveld, AA, Brewer, BJ, Dalla Bontá, E, Lorenzo-Cáceres, AD, Denney, KD, Dietrich, M, Edelson, R, Evans, PA, Fausnaugh, MM, Gehrels, N, Gelbord, JM, Goad, MR, Grier, CJ, Grupe, D, Hall, PB, Kaastra, J, Kelly, BC, Kennea, JA, Kochanek, CS, Lira, P, Mathur, S, McHardy, IM, Nousek, JA, Pancoast, A, Papadakis, I, Pei, L, Schimoia, JS, Siegel, M, Starkey, D, Treu, T, Uttley, P, Vaughan, S, Vestergaard, M, Villforth, C, Yan, H, Young, S, and Zu, Y

Abstract

We describe the first results from a six-month long reverberation-mapping experiment in the ultraviolet based on 171 observations of the Seyfert 1 galaxy NGC 5548 with the Cosmic Origins Spectrograph on the Hubble Space Telescope. Significant correlated variability is found in the continuum and broad emission lines, with amplitudes ranging from ∼30% to a factor of two in the emission lines and a factor of three in the continuum. The variations of all the strong emission lines lag behind those of the continuum, with He ii lagging behind the continuum by ∼2.5 days and Ly , C iv , and Si iv lagging by ∼5-6 days. The relationship between the continuum and emission lines is complex. In particular, during the second half of the campaign, all emission-line lags increased by a factor of 1.3-2 and differences appear in the detailed structure of the continuum and emission-line light curves. Velocity-resolved cross-correlation analysis shows coherent structure in lag versus line of sight velocity for the emission lines; the high-velocity wings of C iv respond to continuum variations more rapidly than the line core, probably indicating higher velocity broad-line region clouds at smaller distances from the central engine. The velocity-dependent response of Ly, however, is more complex and will require further analysis.

Published
2015

14. SPACE TELESCOPE and OPTICAL REVERBERATION MAPPING PROJECT. II. SWIFT and HST REVERBERATION MAPPING of the ACCRETION DISK of NGC 5548

Author

Edelson, R, Edelson, R, Gelbord, JM, Horne, K, McHardy, IM, Peterson, BM, Arévalo, P, Breeveld, AA, Rosa, GD, Evans, PA, Goad, MR, Kriss, GA, Brandt, WN, Gehrels, N, Grupe, D, Kennea, JA, Kochanek, CS, Nousek, JA, Papadakis, I, Siegel, M, Starkey, D, Uttley, P, Vaughan, S, Young, S, Barth, AJ, Bentz, MC, Brewer, BJ, Crenshaw, DM, Dalla Bontà, E, Cáceres, ADL, Denney, KD, Dietrich, M, Ely, J, Fausnaugh, MM, Grier, CJ, Hall, PB, Kaastra, J, Kelly, BC, Korista, KT, Lira, P, Mathur, S, Netzer, H, Pancoast, A, Pei, L, Pogge, RW, Schimoia, JS, Treu, T, Vestergaard, M, Villforth, C, Yan, H, Zu, Y, Edelson, R, Edelson, R, Gelbord, JM, Horne, K, McHardy, IM, Peterson, BM, Arévalo, P, Breeveld, AA, Rosa, GD, Evans, PA, Goad, MR, Kriss, GA, Brandt, WN, Gehrels, N, Grupe, D, Kennea, JA, Kochanek, CS, Nousek, JA, Papadakis, I, Siegel, M, Starkey, D, Uttley, P, Vaughan, S, Young, S, Barth, AJ, Bentz, MC, Brewer, BJ, Crenshaw, DM, Dalla Bontà, E, Cáceres, ADL, Denney, KD, Dietrich, M, Ely, J, Fausnaugh, MM, Grier, CJ, Hall, PB, Kaastra, J, Kelly, BC, Korista, KT, Lira, P, Mathur, S, Netzer, H, Pancoast, A, Pei, L, Pogge, RW, Schimoia, JS, Treu, T, Vestergaard, M, Villforth, C, Yan, H, and Zu, Y

Abstract

Recent intensive Swift monitoring of the Seyfert 1 galaxy NGC 5548 yielded 282 usable epochs over 125 days across six UV/optical bands and the X-rays. This is the densest extended active galactic nucleus (AGN) UV/optical continuum sampling ever obtained, with a mean sampling rate <0.5 day. Approximately daily Hubble Space Telescope UV sampling was also obtained. The UV/optical light curves show strong correlations () and the clearest measurement to date of interband lags. These lags are well-fit by a wavelength dependence, with a normalization that indicates an unexpectedly large disk radius of lt-day at 1367 , assuming a simple face-on model. The U band shows a marginally larger lag than expected from the fit and surrounding bands, which could be due to Balmer continuum emission from the broad-line region as suggested by Korista and Goad. The UV/X-ray correlation is weaker () and less consistent over time. This indicates that while Swift is beginning to measure UV/optical lags in general agreement with accretion disk theory (although the derived size is larger than predicted), the relationship with X-ray variability is less well understood. Combining this accretion disk size estimate with those from quasar microlensing studies suggests that AGN disk sizes scale approximately linearly with central black hole mass over a wide range of masses.

Published
2015

15. Space Telescope and Optical Reverberation Mapping Project. I. Ultraviolet Observations of the Seyfert 1 Galaxy NGC 5548 With the Cosmic Origins Spectrograph on Hubble Space Telescope

Author

De Rosa, G, De Rosa, G, Peterson, BM, Ely, J, Kriss, GA, Crenshaw, DM, Horne, K, Korista, KT, Netzer, H, Pogge, RW, Arévalo, P, Barth, AJ, Bentz, MC, Brandt, WN, Breeveld, AA, Brewer, BJ, Dalla Bontá, E, Lorenzo-Cáceres, AD, Denney, KD, Dietrich, M, Edelson, R, Evans, PA, Fausnaugh, MM, Gehrels, N, Gelbord, JM, Goad, MR, Grier, CJ, Grupe, D, Hall, PB, Kaastra, J, Kelly, BC, Kennea, JA, Kochanek, CS, Lira, P, Mathur, S, McHardy, IM, Nousek, JA, Pancoast, A, Papadakis, I, Pei, L, Schimoia, JS, Siegel, M, Starkey, D, Treu, T, Uttley, P, Vaughan, S, Vestergaard, M, Villforth, C, Yan, H, Young, S, Zu, Y, De Rosa, G, De Rosa, G, Peterson, BM, Ely, J, Kriss, GA, Crenshaw, DM, Horne, K, Korista, KT, Netzer, H, Pogge, RW, Arévalo, P, Barth, AJ, Bentz, MC, Brandt, WN, Breeveld, AA, Brewer, BJ, Dalla Bontá, E, Lorenzo-Cáceres, AD, Denney, KD, Dietrich, M, Edelson, R, Evans, PA, Fausnaugh, MM, Gehrels, N, Gelbord, JM, Goad, MR, Grier, CJ, Grupe, D, Hall, PB, Kaastra, J, Kelly, BC, Kennea, JA, Kochanek, CS, Lira, P, Mathur, S, McHardy, IM, Nousek, JA, Pancoast, A, Papadakis, I, Pei, L, Schimoia, JS, Siegel, M, Starkey, D, Treu, T, Uttley, P, Vaughan, S, Vestergaard, M, Villforth, C, Yan, H, Young, S, and Zu, Y

Abstract

We describe the first results from a six-month long reverberation-mapping experiment in the ultraviolet based on 171 observations of the Seyfert 1 galaxy NGC 5548 with the Cosmic Origins Spectrograph on the Hubble Space Telescope. Significant correlated variability is found in the continuum and broad emission lines, with amplitudes ranging from ∼30% to a factor of two in the emission lines and a factor of three in the continuum. The variations of all the strong emission lines lag behind those of the continuum, with He ii lagging behind the continuum by ∼2.5 days and Ly , C iv , and Si iv lagging by ∼5-6 days. The relationship between the continuum and emission lines is complex. In particular, during the second half of the campaign, all emission-line lags increased by a factor of 1.3-2 and differences appear in the detailed structure of the continuum and emission-line light curves. Velocity-resolved cross-correlation analysis shows coherent structure in lag versus line of sight velocity for the emission lines; the high-velocity wings of C iv respond to continuum variations more rapidly than the line core, probably indicating higher velocity broad-line region clouds at smaller distances from the central engine. The velocity-dependent response of Ly, however, is more complex and will require further analysis.

Published
2015

16. SPACE TELESCOPE and OPTICAL REVERBERATION MAPPING PROJECT. II. SWIFT and HST REVERBERATION MAPPING of the ACCRETION DISK of NGC 5548

Author

Edelson, R, Edelson, R, Gelbord, JM, Horne, K, McHardy, IM, Peterson, BM, Arévalo, P, Breeveld, AA, Rosa, GD, Evans, PA, Goad, MR, Kriss, GA, Brandt, WN, Gehrels, N, Grupe, D, Kennea, JA, Kochanek, CS, Nousek, JA, Papadakis, I, Siegel, M, Starkey, D, Uttley, P, Vaughan, S, Young, S, Barth, AJ, Bentz, MC, Brewer, BJ, Crenshaw, DM, Dalla Bontà, E, Cáceres, ADL, Denney, KD, Dietrich, M, Ely, J, Fausnaugh, MM, Grier, CJ, Hall, PB, Kaastra, J, Kelly, BC, Korista, KT, Lira, P, Mathur, S, Netzer, H, Pancoast, A, Pei, L, Pogge, RW, Schimoia, JS, Treu, T, Vestergaard, M, Villforth, C, Yan, H, Zu, Y, Edelson, R, Edelson, R, Gelbord, JM, Horne, K, McHardy, IM, Peterson, BM, Arévalo, P, Breeveld, AA, Rosa, GD, Evans, PA, Goad, MR, Kriss, GA, Brandt, WN, Gehrels, N, Grupe, D, Kennea, JA, Kochanek, CS, Nousek, JA, Papadakis, I, Siegel, M, Starkey, D, Uttley, P, Vaughan, S, Young, S, Barth, AJ, Bentz, MC, Brewer, BJ, Crenshaw, DM, Dalla Bontà, E, Cáceres, ADL, Denney, KD, Dietrich, M, Ely, J, Fausnaugh, MM, Grier, CJ, Hall, PB, Kaastra, J, Kelly, BC, Korista, KT, Lira, P, Mathur, S, Netzer, H, Pancoast, A, Pei, L, Pogge, RW, Schimoia, JS, Treu, T, Vestergaard, M, Villforth, C, Yan, H, and Zu, Y

Abstract

Recent intensive Swift monitoring of the Seyfert 1 galaxy NGC 5548 yielded 282 usable epochs over 125 days across six UV/optical bands and the X-rays. This is the densest extended active galactic nucleus (AGN) UV/optical continuum sampling ever obtained, with a mean sampling rate <0.5 day. Approximately daily Hubble Space Telescope UV sampling was also obtained. The UV/optical light curves show strong correlations () and the clearest measurement to date of interband lags. These lags are well-fit by a wavelength dependence, with a normalization that indicates an unexpectedly large disk radius of lt-day at 1367 , assuming a simple face-on model. The U band shows a marginally larger lag than expected from the fit and surrounding bands, which could be due to Balmer continuum emission from the broad-line region as suggested by Korista and Goad. The UV/X-ray correlation is weaker () and less consistent over time. This indicates that while Swift is beginning to measure UV/optical lags in general agreement with accretion disk theory (although the derived size is larger than predicted), the relationship with X-ray variability is less well understood. Combining this accretion disk size estimate with those from quasar microlensing studies suggests that AGN disk sizes scale approximately linearly with central black hole mass over a wide range of masses.

Published
2015

17. This title is unavailable for guests, please login to see more information.

Author

Santos-Lleó, M, Santos-Lleó, M, Clavel, J, Schulz, B, Altieri, B, Barr, P, Alloin, D, Berlind, P, Bertram, R, Crenshaw, DM, Edelson, RA, Giveon, U, Horne, K, Huchra, JP, Kaspi, S, Kriss, GA, Krolik, JH, Malkan, MA, Malkov, Yu F, Netzer, H, O'Brien, PT, Peterson, BM, Pogge, RW, Pronik, VI, Qian, B-C, Reichert, GA, Rodríguez-Pascual, PM, Sergeev, SG, Tao, J, Tokarz, S, Wagner, RM, Wamsteker, W, Wilkes, BJ, Santos-Lleó, M, Santos-Lleó, M, Clavel, J, Schulz, B, Altieri, B, Barr, P, Alloin, D, Berlind, P, Bertram, R, Crenshaw, DM, Edelson, RA, Giveon, U, Horne, K, Huchra, JP, Kaspi, S, Kriss, GA, Krolik, JH, Malkan, MA, Malkov, Yu F, Netzer, H, O'Brien, PT, Peterson, BM, Pogge, RW, Pronik, VI, Qian, B-C, Reichert, GA, Rodríguez-Pascual, PM, Sergeev, SG, Tao, J, Tokarz, S, Wagner, RM, Wamsteker, W, and Wilkes, BJ

Published
2001

18. Steps toward Determination of the Size and Structure of the Broad-Line Region in Active Galactic Nuclei. IX. Ultraviolet Observations of Fairall 9

Author

Rodríguez-Pascual, PM, Rodríguez-Pascual, PM, Alloin, D, Clavel, J, Crenshaw, DM, Horne, K, Kriss, GA, Krolik, JH, Malkan, MA, Netzer, H, O'Brien, PT, Peterson, BM, Reichert, GA, Wamsteker, W, Alexander, T, Barr, P, Blandford, RD, Bregman, JN, Carone, TE, Clements, S, Courvoisier, T-J, De Robertis, MM, Dietrich, M, Dottori, H, Edelson, RA, Filippenko, AV, Gaskell, CM, Huchra, JP, Hutchings, JB, Kollatschny, W, Koratkar, AP, Korista, KT, Laor, A, MacAlpine, GM, Martin, PG, Maoz, D, McCollum, B, Morris, SL, Perola, GC, Pogge, RW, Ptak, RL, Recondo-González, MC, Rodríguez-Espinoza, JM, Rokaki, EL, Santos-Lleó, M, Sekiguchi, K, Shull, JM, Snijders, MAJ, Sparke, LS, Stirpe, GM, Stoner, RE, Sun, W-H, Wagner, SJ, Wanders, I, Wilkes, J, Winge, C, Zheng, W, Rodríguez-Pascual, PM, Rodríguez-Pascual, PM, Alloin, D, Clavel, J, Crenshaw, DM, Horne, K, Kriss, GA, Krolik, JH, Malkan, MA, Netzer, H, O'Brien, PT, Peterson, BM, Reichert, GA, Wamsteker, W, Alexander, T, Barr, P, Blandford, RD, Bregman, JN, Carone, TE, Clements, S, Courvoisier, T-J, De Robertis, MM, Dietrich, M, Dottori, H, Edelson, RA, Filippenko, AV, Gaskell, CM, Huchra, JP, Hutchings, JB, Kollatschny, W, Koratkar, AP, Korista, KT, Laor, A, MacAlpine, GM, Martin, PG, Maoz, D, McCollum, B, Morris, SL, Perola, GC, Pogge, RW, Ptak, RL, Recondo-González, MC, Rodríguez-Espinoza, JM, Rokaki, EL, Santos-Lleó, M, Sekiguchi, K, Shull, JM, Snijders, MAJ, Sparke, LS, Stirpe, GM, Stoner, RE, Sun, W-H, Wagner, SJ, Wanders, I, Wilkes, J, Winge, C, and Zheng, W

Published
1997

19. Multiwavelength observations of short-timescale variability in NGC 4151 .4. Analysis of multiwavelength continuum variability

Author

Edelson, RA, Alexander, T, Crenshaw, DM, Kaspi, S, Malkan, MA, Peterson, BM, Warwick, RS, Clavel, J, Filippenko, AV, Horne, K, Korista, KT, Kriss, GA, Krolik, JH, Maoz, D, Nandra, K, OBrien, PT, Penton, SV, Yaqoob, T, Albrecht, P, Alloin, D, Ayres, TR, Balonek, TJ, Barr, P, Bar, Edelson, RA, Alexander, T, Crenshaw, DM, Kaspi, S, Malkan, MA, Peterson, BM, Warwick, RS, Clavel, J, Filippenko, AV, Horne, K, Korista, KT, Kriss, GA, Krolik, JH, Maoz, D, Nandra, K, OBrien, PT, Penton, SV, Yaqoob, T, Albrecht, P, Alloin, D, Ayres, TR, Balonek, TJ, Barr, P, and Bar

Abstract

This paper combines data from the three preceding papers in order to analyze the multi-wave-band variability and spectral energy distribution of the Seyfert 1 galaxy NGC 4151 during the 1993 December monitoring campaign. The source, which was near its pea, Addresses: Edelson RA, UNIV IOWA, DEPT PHYS & ASTRON, 203 VAN ALLEN, IOWA CITY, IA 52242. TEL AVIV UNIV, SACKLER FAC EXACT SCI, SCH PHYS & ASTRON, IL-69978 TEL AVIV, ISRAEL. TEL AVIV UNIV, SACKLER FAC EXACT SCI, WISE OBSERV, IL-69978 TEL AVIV, ISRAEL. NAS

Published
1996

20. STEPS TOWARD DETERMINATION OF THE SIZE AND STRUCTURE OF THE BROAD-LINE REGION IN ACTIVE GALACTIC NUCLEI .8. AN INTENSIVE HST, IUE, AND GROUND-BASED STUDY OF NGC-5548

Author

KORISTA, KT, ALLOIN, D, BARR, P, CLAVEL, J, COHEN, RD, CRENSHAW, DM, EVANS, IN, HORNE, K, KORATKAR, AP, KRISS, GA, KROLIK, JH, MALKAN, MA, MORRIS, SL, NETZER, H, OBRIEN, PT, PETERSON, BM, REICHERT, GA, RODRIGUEZPASCUAL, PM, WAMSTEKER, W, ANDERSON, KSJ, AXON, DJ, BENITEZ, E, BE, KORISTA, KT, ALLOIN, D, BARR, P, CLAVEL, J, COHEN, RD, CRENSHAW, DM, EVANS, IN, HORNE, K, KORATKAR, AP, KRISS, GA, KROLIK, JH, MALKAN, MA, MORRIS, SL, NETZER, H, OBRIEN, PT, PETERSON, BM, REICHERT, GA, RODRIGUEZPASCUAL, PM, WAMSTEKER, W, ANDERSON, KSJ, AXON, DJ, BENITEZ, E, and BE

Abstract

We present the data and initial results from a combined HST/IUE/ground-based spectroscopic monitoring campaign on the Seyfert 1 galaxy NGC 5548 that was undertaken in order to address questions that require both higher temporal resolution and higher signa, Addresses: SPACE TELESCOPE SCI INST, BALTIMORE, MD 21218. OBSERV PARIS, CNRS, URA 173, F-92195 MEUDON, FRANCE. EUROPEAN SPACE TECHNOL CTR, EUROPEAN SPACE AGCY, DIV ASTROPHYS, ISO OBSERV, 2200 AG NOORDWIJK, NETHERLANDS. UNIV CALIF SAN DIEGO, CTR ASTROPHYS

Published
1995

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