_version_ 1866910634245881856
author Netzer, Hagai
Goad, Michael R.
Barth, Aaron J.
Cackett, Edward M.
Horne, Keith
Hu, Chen
Kara, Erin
Korista, Kirk T.
Kriss, Gerard A.
Lewin, Collin
Montano, John
Arav, Nahum
Behar, Ehud
Brotherton, Michael S.
Chelouche, Doron
de Rosa, Gisella
Bonta, Elena Dalla
Dehghanian, Maryam
Ferland, Gary J.
Fian, Carina
Homayouni, Yasaman
Ilic, Dragana
Kaspi, Shai
Kovacevic, Andjelka B.
Landt, Hermine
Popovic, Luka C.
Storchi-Bergmann, Thaisa
Wang, Jian-Min
Zaidouni, Fatima
author_facet Netzer, Hagai
Goad, Michael R.
Barth, Aaron J.
Cackett, Edward M.
Horne, Keith
Hu, Chen
Kara, Erin
Korista, Kirk T.
Kriss, Gerard A.
Lewin, Collin
Montano, John
Arav, Nahum
Behar, Ehud
Brotherton, Michael S.
Chelouche, Doron
de Rosa, Gisella
Bonta, Elena Dalla
Dehghanian, Maryam
Ferland, Gary J.
Fian, Carina
Homayouni, Yasaman
Ilic, Dragana
Kaspi, Shai
Kovacevic, Andjelka B.
Landt, Hermine
Popovic, Luka C.
Storchi-Bergmann, Thaisa
Wang, Jian-Min
Zaidouni, Fatima
contents The local (z=0.0315) AGN Mrk 817, was monitored over more than 500 days with space-borne and ground-based instruments as part of a large international campaign AGN STORM 2. Here, we present a comprehensive analysis of the broad-band continuum variations using detailed modeling of the broad line region (BLR), several types of disk winds classified by their optical depth, and new numerical simulations. We find that diffuse continuum (DC) emission, with additional contributions from strong and broad emission lines, can explain the continuum lags observed in this source during high and low luminosity phases. Disk illumination by the variable X-ray corona contributes only a small fraction of the observed continuum lags. Our BLR models assume radiation pressure-confined clouds distributed over a distance of 2-122 light days. We present calculated mean-emissivity radii of many emission lines, and DC emission, and suggest a simple, transfer-function-dependent method that ties them to cross-correlation lag determinations. We do not find clear indications for large optical depth winds but identify the signature of lower column density winds. In particular, we associate the shortest observed continuum lags with a combination of tau(1 Ryd) approx. 2 wind and a partly shielded BLR. Even smaller optical depth winds may be associated with X-ray absorption features and with noticeable variations in the width and lags of several high ionization lines like HeII and CIV. Finally, we demonstrate the effect of torus dust emission on the observed lags in the i and z bands.
format Preprint
id arxiv_https___arxiv_org_abs_2410_02652
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle AGN STORM 2: X. The origin of the interband continuum delays in Mrk 817
Netzer, Hagai
Goad, Michael R.
Barth, Aaron J.
Cackett, Edward M.
Horne, Keith
Hu, Chen
Kara, Erin
Korista, Kirk T.
Kriss, Gerard A.
Lewin, Collin
Montano, John
Arav, Nahum
Behar, Ehud
Brotherton, Michael S.
Chelouche, Doron
de Rosa, Gisella
Bonta, Elena Dalla
Dehghanian, Maryam
Ferland, Gary J.
Fian, Carina
Homayouni, Yasaman
Ilic, Dragana
Kaspi, Shai
Kovacevic, Andjelka B.
Landt, Hermine
Popovic, Luka C.
Storchi-Bergmann, Thaisa
Wang, Jian-Min
Zaidouni, Fatima
Astrophysics of Galaxies
The local (z=0.0315) AGN Mrk 817, was monitored over more than 500 days with space-borne and ground-based instruments as part of a large international campaign AGN STORM 2. Here, we present a comprehensive analysis of the broad-band continuum variations using detailed modeling of the broad line region (BLR), several types of disk winds classified by their optical depth, and new numerical simulations. We find that diffuse continuum (DC) emission, with additional contributions from strong and broad emission lines, can explain the continuum lags observed in this source during high and low luminosity phases. Disk illumination by the variable X-ray corona contributes only a small fraction of the observed continuum lags. Our BLR models assume radiation pressure-confined clouds distributed over a distance of 2-122 light days. We present calculated mean-emissivity radii of many emission lines, and DC emission, and suggest a simple, transfer-function-dependent method that ties them to cross-correlation lag determinations. We do not find clear indications for large optical depth winds but identify the signature of lower column density winds. In particular, we associate the shortest observed continuum lags with a combination of tau(1 Ryd) approx. 2 wind and a partly shielded BLR. Even smaller optical depth winds may be associated with X-ray absorption features and with noticeable variations in the width and lags of several high ionization lines like HeII and CIV. Finally, we demonstrate the effect of torus dust emission on the observed lags in the i and z bands.
title AGN STORM 2: X. The origin of the interband continuum delays in Mrk 817
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2410.02652