NuSTAR observations of water megamaser AGN

A. Masini, A. Comastri, M. Balokovic, I. Zaw, S. Puccetti, D. R. Ballantyne, F. E. Bauer, S. E. Boggs, W. N. Brandt, M. Brightman, Finn Erland Christensen, W. W. Craig, P. Gandhi, C. J. Hailey, F. A. Harrison, M. J. Koss, G. Madejski, C. Ricci, E. Rivers, D. Stern & 1 others W. W. Zhang

Research output: Contribution to journalJournal articleResearchpeer-review

134 Downloads (Pure)

Abstract

Aims. We study the connection between the masing disk and obscuring torus in Seyfert 2 galaxies.
Methods. We present a uniform X-ray spectral analysis of the high energy properties of 14 nearby megamaser active galactic nuclei observed by NuSTAR. We use a simple analytical model to localize the maser disk and understand its connection with the torus by combining NuSTAR spectral parameters with the available physical quantities from VLBI mapping.
Results. Most of the sources that we analyzed are heavily obscured, showing a column density in excess of similar to 1023 cm-2; in particular, 79% are Compton-thick (NH > 1.5 x 1024 cm-2). When using column densities measured by NuSTAR with the assumption that the torus is the extension of the maser disk, and further assuming a reasonable density profile, we can predict the torus dimensions. They are found to be consistent with mid-IR interferometry parsec-scale observations of Circinus and NGC 1068. In this picture, the maser disk is intimately connected to the inner part of the torus. It is probably made of a large number of molecular clouds that connect the torus and the outer part of the accretion disk, giving rise to a thin disk rotating in most cases in Keplerian or sub-Keplerian motion. This toy model explains the established close connection between water megamaser emission and nuclear obscuration as a geometric effect.
Original languageEnglish
Article numberA59
JournalAstronomy & Astrophysics
Volume589
Number of pages14
ISSN0004-6361
DOIs
Publication statusPublished - 2016

Cite this

Masini, A., Comastri, A., Balokovic, M., Zaw, I., Puccetti, S., Ballantyne, D. R., ... Zhang, W. W. (2016). NuSTAR observations of water megamaser AGN. Astronomy & Astrophysics, 589, [A59]. https://doi.org/10.1051/0004-6361/201527689
Masini, A. ; Comastri, A. ; Balokovic, M. ; Zaw, I. ; Puccetti, S. ; Ballantyne, D. R. ; Bauer, F. E. ; Boggs, S. E. ; Brandt, W. N. ; Brightman, M. ; Christensen, Finn Erland ; Craig, W. W. ; Gandhi, P. ; Hailey, C. J. ; Harrison, F. A. ; Koss, M. J. ; Madejski, G. ; Ricci, C. ; Rivers, E. ; Stern, D. ; Zhang, W. W. / NuSTAR observations of water megamaser AGN. In: Astronomy & Astrophysics. 2016 ; Vol. 589.
@article{2748bd50173c4f12873232337bd3975f,
title = "NuSTAR observations of water megamaser AGN",
abstract = "Aims. We study the connection between the masing disk and obscuring torus in Seyfert 2 galaxies.Methods. We present a uniform X-ray spectral analysis of the high energy properties of 14 nearby megamaser active galactic nuclei observed by NuSTAR. We use a simple analytical model to localize the maser disk and understand its connection with the torus by combining NuSTAR spectral parameters with the available physical quantities from VLBI mapping.Results. Most of the sources that we analyzed are heavily obscured, showing a column density in excess of similar to 1023 cm-2; in particular, 79{\%} are Compton-thick (NH > 1.5 x 1024 cm-2). When using column densities measured by NuSTAR with the assumption that the torus is the extension of the maser disk, and further assuming a reasonable density profile, we can predict the torus dimensions. They are found to be consistent with mid-IR interferometry parsec-scale observations of Circinus and NGC 1068. In this picture, the maser disk is intimately connected to the inner part of the torus. It is probably made of a large number of molecular clouds that connect the torus and the outer part of the accretion disk, giving rise to a thin disk rotating in most cases in Keplerian or sub-Keplerian motion. This toy model explains the established close connection between water megamaser emission and nuclear obscuration as a geometric effect.",
author = "A. Masini and A. Comastri and M. Balokovic and I. Zaw and S. Puccetti and Ballantyne, {D. R.} and Bauer, {F. E.} and Boggs, {S. E.} and Brandt, {W. N.} and M. Brightman and Christensen, {Finn Erland} and Craig, {W. W.} and P. Gandhi and Hailey, {C. J.} and Harrison, {F. A.} and Koss, {M. J.} and G. Madejski and C. Ricci and E. Rivers and D. Stern and Zhang, {W. W.}",
year = "2016",
doi = "10.1051/0004-6361/201527689",
language = "English",
volume = "589",
journal = "Astronomy & Astrophysics",
issn = "0004-6361",
publisher = "E D P Sciences",

}

Masini, A, Comastri, A, Balokovic, M, Zaw, I, Puccetti, S, Ballantyne, DR, Bauer, FE, Boggs, SE, Brandt, WN, Brightman, M, Christensen, FE, Craig, WW, Gandhi, P, Hailey, CJ, Harrison, FA, Koss, MJ, Madejski, G, Ricci, C, Rivers, E, Stern, D & Zhang, WW 2016, 'NuSTAR observations of water megamaser AGN', Astronomy & Astrophysics, vol. 589, A59. https://doi.org/10.1051/0004-6361/201527689

NuSTAR observations of water megamaser AGN. / Masini, A.; Comastri, A.; Balokovic, M.; Zaw, I.; Puccetti, S.; Ballantyne, D. R.; Bauer, F. E.; Boggs, S. E.; Brandt, W. N.; Brightman, M.; Christensen, Finn Erland; Craig, W. W.; Gandhi, P.; Hailey, C. J.; Harrison, F. A.; Koss, M. J.; Madejski, G.; Ricci, C.; Rivers, E.; Stern, D.; Zhang, W. W.

In: Astronomy & Astrophysics, Vol. 589, A59, 2016.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - NuSTAR observations of water megamaser AGN

AU - Masini, A.

AU - Comastri, A.

AU - Balokovic, M.

AU - Zaw, I.

AU - Puccetti, S.

AU - Ballantyne, D. R.

AU - Bauer, F. E.

AU - Boggs, S. E.

AU - Brandt, W. N.

AU - Brightman, M.

AU - Christensen, Finn Erland

AU - Craig, W. W.

AU - Gandhi, P.

AU - Hailey, C. J.

AU - Harrison, F. A.

AU - Koss, M. J.

AU - Madejski, G.

AU - Ricci, C.

AU - Rivers, E.

AU - Stern, D.

AU - Zhang, W. W.

PY - 2016

Y1 - 2016

N2 - Aims. We study the connection between the masing disk and obscuring torus in Seyfert 2 galaxies.Methods. We present a uniform X-ray spectral analysis of the high energy properties of 14 nearby megamaser active galactic nuclei observed by NuSTAR. We use a simple analytical model to localize the maser disk and understand its connection with the torus by combining NuSTAR spectral parameters with the available physical quantities from VLBI mapping.Results. Most of the sources that we analyzed are heavily obscured, showing a column density in excess of similar to 1023 cm-2; in particular, 79% are Compton-thick (NH > 1.5 x 1024 cm-2). When using column densities measured by NuSTAR with the assumption that the torus is the extension of the maser disk, and further assuming a reasonable density profile, we can predict the torus dimensions. They are found to be consistent with mid-IR interferometry parsec-scale observations of Circinus and NGC 1068. In this picture, the maser disk is intimately connected to the inner part of the torus. It is probably made of a large number of molecular clouds that connect the torus and the outer part of the accretion disk, giving rise to a thin disk rotating in most cases in Keplerian or sub-Keplerian motion. This toy model explains the established close connection between water megamaser emission and nuclear obscuration as a geometric effect.

AB - Aims. We study the connection between the masing disk and obscuring torus in Seyfert 2 galaxies.Methods. We present a uniform X-ray spectral analysis of the high energy properties of 14 nearby megamaser active galactic nuclei observed by NuSTAR. We use a simple analytical model to localize the maser disk and understand its connection with the torus by combining NuSTAR spectral parameters with the available physical quantities from VLBI mapping.Results. Most of the sources that we analyzed are heavily obscured, showing a column density in excess of similar to 1023 cm-2; in particular, 79% are Compton-thick (NH > 1.5 x 1024 cm-2). When using column densities measured by NuSTAR with the assumption that the torus is the extension of the maser disk, and further assuming a reasonable density profile, we can predict the torus dimensions. They are found to be consistent with mid-IR interferometry parsec-scale observations of Circinus and NGC 1068. In this picture, the maser disk is intimately connected to the inner part of the torus. It is probably made of a large number of molecular clouds that connect the torus and the outer part of the accretion disk, giving rise to a thin disk rotating in most cases in Keplerian or sub-Keplerian motion. This toy model explains the established close connection between water megamaser emission and nuclear obscuration as a geometric effect.

U2 - 10.1051/0004-6361/201527689

DO - 10.1051/0004-6361/201527689

M3 - Journal article

VL - 589

JO - Astronomy & Astrophysics

JF - Astronomy & Astrophysics

SN - 0004-6361

M1 - A59

ER -

Masini A, Comastri A, Balokovic M, Zaw I, Puccetti S, Ballantyne DR et al. NuSTAR observations of water megamaser AGN. Astronomy & Astrophysics. 2016;589. A59. https://doi.org/10.1051/0004-6361/201527689