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

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; S. M. Crawford; Elena Dalla Bontà; D. Emmanoulopoulos; P. Evans; R. Figuera Jaimes; A. V. Filippenko; G. Ferland; D. Grupe; M. Joner; J. Kennea; K. T. Korista; H. A. Krimm; G. Kriss; D. C. Leonard; S. Mathur; H. Netzer; J. Nousek; K. Page; E. Romero-Colmenero; M. Siegel; D. A. Starkey; T. Treu; H. A. Vogler; H. Winkler; W. Zheng

doi:10.3847/1538-4357/aa6890

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

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
, S. M. Crawford

Elena Dalla Bontà, D. Emmanoulopoulos, P. Evans, R. Figuera Jaimes, A. V. Filippenko, G. Ferland, D. Grupe, M. Joner, J. Kennea, K. T. Korista, H. A. Krimm, G. Kriss, D. C. Leonard, S. Mathur, H. Netzer, J. Nousek, K. Page, E. Romero-Colmenero, M. Siegel, D. A. Starkey, T. Treu, H. A. Vogler, H. Winkler, W. Zheng

Producción científica: Article › revisión exhaustiva

137 Citas (Scopus)

Resumen

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.

Idioma original	English
Número de artículo	41
Publicación	Astrophysical Journal
Volumen	840
N.º	1
DOI	https://doi.org/10.3847/1538-4357/aa6890
Estado	Published - may 1 2017

Nota bibliográfica

Publisher Copyright:
© 2017. The American Astronomical Society. All rights reserved.

Financiación

R.E. gratefully acknowledges support from NASA under awards NNX13AC26G, NNX13AC63G, and NNX13AE99G. J.M.G. acknowledges support from NASA under award NNH13CH61C. Research by A.J.B. and H.A.V. was supported by NSF grant AST-1412693. K.H. acknowledges support from STFC grant ST/M001296/1. M.B. gratefully acknowledges support from the NSF through CAREER grant AST-1253702. S.M.C. and E.R.C. gratefully acknowledge the receipt of research grants from the National Research Foundation (NRF) of South Africa. P.E. and K.P. acknowledge support from the UK Space Agency. A.V.F. and W.Z. are grateful for financial assistance from NSF grant AST-1211916, the TABASGO Foundation, and the Christopher R. Redlich Fund. D.C.L. gratefully acknowledges support from NSF under grants AST-1009571 and AST-1210311. T.T. has been supported by NSF grant AST-1412315 and by the Packard Foundation in the form of a Packard Research Fellowship. M.V. gratefully acknowledges support from the Danish Council for Independent Research via grant no. DFF 4002-00275.

Financiadores	Número del financiador
TABASGO Foundation
David and Lucile Packard Foundation
National Research Foundation South African Research Chair
UK Industrial Decarbonization Research and Innovation Centre
???publication-publication-funding-organisation-not-added???	ST/P002218/1, ST/P006892/1, ST/L005654/1, ST/P000541/1, ST/N000811/1, ST/M003035/1, AST-1253702, ST/M001296/1
National Science Foundation Arctic Social Science Program	AST-1412693, 1412315, 1412155, 1253702, 1210311
Christopher R. Redlich Fund	AST-1412315, AST-1009571, AST-1210311
National Aeronautics and Space Administration	NNH13CH61C, NNX13AC63G, NNX13AE99G, NNX13AC26G
UK Space Agency	AST-1211916
Natur og Univers, Det Frie Forskningsråd	DFF 4002-00275

ASJC Scopus subject areas

Astronomy and Astrophysics
Space and Planetary Science

Acceder al documento

10.3847/1538-4357/aa6890

Otros archivos y enlaces

Citar esto

Edelson, R., Gelbord, J., Cackett, E., Connolly, S., Done, C., Fausnaugh, M., Gardner, E., Gehrels, N., Goad, M., Horne, K., McHardy, I., Peterson, B. M., Vaughan, S., Vestergaard, M., Breeveld, A., Barth, A. J., Bentz, M., Bottorff, M., Brandt, W. N., ... Zheng, W. (2017). Swift Monitoring of NGC 4151: Evidence for a Second X-Ray/UV Reprocessing. Astrophysical Journal, 840(1), Artículo 41. https://doi.org/10.3847/1538-4357/aa6890

@article{e833af5dd60d435aa6afbdb5a8aa3242,

title = "Swift Monitoring of NGC 4151: Evidence for a Second X-Ray/UV Reprocessing",

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 {\AA}). 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.",

keywords = "galaxies: Seyfert, galaxies: active, galaxies: individual (NGC 4151), galaxies: nuclei",

author = "R. Edelson and J. Gelbord and E. Cackett and S. Connolly and C. Done and M. Fausnaugh and E. Gardner and N. Gehrels and M. Goad and K. Horne and I. McHardy and Peterson, \{B. M.\} and S. Vaughan and M. Vestergaard and A. Breeveld and Barth, \{A. J.\} and M. Bentz and M. Bottorff and Brandt, \{W. N.\} and Crawford, \{S. M.\} and \{Dalla Bont{\`a}\}, Elena and D. Emmanoulopoulos and P. Evans and Jaimes, \{R. Figuera\} and Filippenko, \{A. V.\} and G. Ferland and D. Grupe and M. Joner and J. Kennea and Korista, \{K. T.\} and Krimm, \{H. A.\} and G. Kriss and Leonard, \{D. C.\} and S. Mathur and H. Netzer and J. Nousek and K. Page and E. Romero-Colmenero and M. Siegel and Starkey, \{D. A.\} and T. Treu and Vogler, \{H. A.\} and H. Winkler and W. Zheng",

year = "2017",

month = may,

day = "1",

doi = "10.3847/1538-4357/aa6890",

language = "English",

volume = "840",

number = "1",

}

Edelson, R, Gelbord, J, Cackett, E, Connolly, S, Done, C, Fausnaugh, M, Gardner, E, Gehrels, N, Goad, M, Horne, K, McHardy, I, Peterson, BM, Vaughan, S, Vestergaard, M, Breeveld, A, Barth, AJ, Bentz, M, Bottorff, M, Brandt, WN, Crawford, SM, Dalla Bontà, E, Emmanoulopoulos, D, Evans, P, Jaimes, RF, Filippenko, AV, Ferland, G, Grupe, D, Joner, M, Kennea, J, Korista, KT, Krimm, HA, Kriss, G, Leonard, DC, Mathur, S, Netzer, H, Nousek, J, Page, K, Romero-Colmenero, E, Siegel, M, Starkey, DA, Treu, T, Vogler, HA, Winkler, H & Zheng, W 2017, 'Swift Monitoring of NGC 4151: Evidence for a Second X-Ray/UV Reprocessing', Astrophysical Journal, vol. 840, n.º 1, 41. https://doi.org/10.3847/1538-4357/aa6890

TY - JOUR

T1 - Swift Monitoring of NGC 4151

T2 - Evidence for a Second X-Ray/UV Reprocessing

AU - Edelson, R.

AU - Gelbord, J.

AU - Cackett, E.

AU - Connolly, S.

AU - Done, C.

AU - Fausnaugh, M.

AU - Gardner, E.

AU - Gehrels, N.

AU - Goad, M.

AU - Horne, K.

AU - McHardy, I.

AU - Peterson, B. M.

AU - Vaughan, S.

AU - Vestergaard, M.

AU - Breeveld, A.

AU - Barth, A. J.

AU - Bentz, M.

AU - Bottorff, M.

AU - Brandt, W. N.

AU - Crawford, S. M.

AU - Dalla Bontà, Elena

AU - Emmanoulopoulos, D.

AU - Evans, P.

AU - Jaimes, R. Figuera

AU - Filippenko, A. V.

AU - Ferland, G.

AU - Grupe, D.

AU - Joner, M.

AU - Kennea, J.

AU - Korista, K. T.

AU - Krimm, H. A.

AU - Kriss, G.

AU - Leonard, D. C.

AU - Mathur, S.

AU - Netzer, H.

AU - Nousek, J.

AU - Page, K.

AU - Romero-Colmenero, E.

AU - Siegel, M.

AU - Starkey, D. A.

AU - Treu, T.

AU - Vogler, H. A.

AU - Winkler, H.

AU - Zheng, W.

PY - 2017/5/1

Y1 - 2017/5/1

N2 - 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.

AB - 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.

KW - galaxies: Seyfert

KW - galaxies: active

KW - galaxies: individual (NGC 4151)

KW - galaxies: nuclei

UR - https://www.scopus.com/pages/publications/85019146385

UR - https://www.scopus.com/pages/publications/85019146385#tab=citedBy

U2 - 10.3847/1538-4357/aa6890

DO - 10.3847/1538-4357/aa6890

M3 - Article

AN - SCOPUS:85019146385

SN - 0004-637X

VL - 840

JO - Astrophysical Journal

JF - Astrophysical Journal

IS - 1

M1 - 41

ER -

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

Resumen

Nota bibliográfica

Financiación

ASJC Scopus subject areas

Acceder al documento

Otros archivos y enlaces

Huella

Citar esto