_version_ 1866910500094214144
author Zaidouni, Fatima
Kara, Erin
Kosec, Peter
Mehdipour, Missagh
Rogantini, Daniele
Kriss, Gerard A.
Behar, Ehud
Kaastra, Jelle
Barth, Aaron J.
Cackett, Edward M.
De Rosa, Gisella
Homayouni, Yasaman
Horne, Keith
Landt, Hermine
Arav, Nahum
Bentz, Misty C.
Brotherton, Michael S.
Bontà, Elena Dalla
Dehghanian, Maryam
Ferland, Gary J.
Fian, Carina
Gelbord, Jonathan
Goad, Michael R.
Buitrago, Diego H. González
Grier, Catherine J.
Hall, Patrick B.
Hu, Chen
Ilić, Dragana
Kaspi, Shai
Kochanek, Christopher S.
Kovačević, Andjelka B.
Kynoch, Daniel
Lewin, Collin
Montano, John
Netzer, Hagai
Neustadt, Jack M. M.
Panagiotou, Christos
Partington, Ethan R.
Plesha, Rachel
Popović, Luka Č.
Proga, Daniel
Storchi-Bergmann, Thaisa
Sanmartim, David
Siebert, Matthew R.
Signorini, Matilde
Vestergaard, Marianne
Waters, Tim
Zu, Ying
author_facet Zaidouni, Fatima
Kara, Erin
Kosec, Peter
Mehdipour, Missagh
Rogantini, Daniele
Kriss, Gerard A.
Behar, Ehud
Kaastra, Jelle
Barth, Aaron J.
Cackett, Edward M.
De Rosa, Gisella
Homayouni, Yasaman
Horne, Keith
Landt, Hermine
Arav, Nahum
Bentz, Misty C.
Brotherton, Michael S.
Bontà, Elena Dalla
Dehghanian, Maryam
Ferland, Gary J.
Fian, Carina
Gelbord, Jonathan
Goad, Michael R.
Buitrago, Diego H. González
Grier, Catherine J.
Hall, Patrick B.
Hu, Chen
Ilić, Dragana
Kaspi, Shai
Kochanek, Christopher S.
Kovačević, Andjelka B.
Kynoch, Daniel
Lewin, Collin
Montano, John
Netzer, Hagai
Neustadt, Jack M. M.
Panagiotou, Christos
Partington, Ethan R.
Plesha, Rachel
Popović, Luka Č.
Proga, Daniel
Storchi-Bergmann, Thaisa
Sanmartim, David
Siebert, Matthew R.
Signorini, Matilde
Vestergaard, Marianne
Waters, Tim
Zu, Ying
contents We present the results of the XMM-Newton and NuSTAR observations taken as part of the ongoing, intensive multi-wavelength monitoring program of the Seyfert 1 galaxy Mrk 817 by the AGN Space Telescope and Optical Reverberation Mapping 2 (AGN STORM 2) Project. The campaign revealed an unexpected and transient obscuring outflow, never before seen in this source. Of our four XMM-Newton/NuSTAR epochs, one fortuitously taken during a bright X-ray state has strong narrow absorption lines in the high-resolution grating spectra. From these absorption features, we determine that the obscurer is in fact a multi-phase ionized wind with an outflow velocity of $\sim$5200 km s$^{-1}$, and for the first time find evidence for a lower ionization component with the same velocity observed in absorption features in the contemporaneous HST spectra. This indicates that the UV absorption troughs may be due to dense clumps embedded in diffuse, higher ionization gas responsible for the X-ray absorption lines of the same velocity. We observe variability in the shape of the absorption lines on timescales of hours, placing the variable component at roughly 1000 $R_g$ if attributed to transverse motion along the line of sight. This estimate aligns with independent UV measurements of the distance to the obscurer suggesting an accretion disk wind at the inner broad line region. We estimate that it takes roughly 200 days for the outflow to travel from the disk to our line of sight, consistent with the timescale of the outflow's column density variations throughout the campaign.
format Preprint
id arxiv_https___arxiv_org_abs_2406_17061
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle AGN STORM 2: IX. Studying the Dynamics of the Ionized Obscurer in Mrk 817 with High-resolution X-ray Spectroscopy
Zaidouni, Fatima
Kara, Erin
Kosec, Peter
Mehdipour, Missagh
Rogantini, Daniele
Kriss, Gerard A.
Behar, Ehud
Kaastra, Jelle
Barth, Aaron J.
Cackett, Edward M.
De Rosa, Gisella
Homayouni, Yasaman
Horne, Keith
Landt, Hermine
Arav, Nahum
Bentz, Misty C.
Brotherton, Michael S.
Bontà, Elena Dalla
Dehghanian, Maryam
Ferland, Gary J.
Fian, Carina
Gelbord, Jonathan
Goad, Michael R.
Buitrago, Diego H. González
Grier, Catherine J.
Hall, Patrick B.
Hu, Chen
Ilić, Dragana
Kaspi, Shai
Kochanek, Christopher S.
Kovačević, Andjelka B.
Kynoch, Daniel
Lewin, Collin
Montano, John
Netzer, Hagai
Neustadt, Jack M. M.
Panagiotou, Christos
Partington, Ethan R.
Plesha, Rachel
Popović, Luka Č.
Proga, Daniel
Storchi-Bergmann, Thaisa
Sanmartim, David
Siebert, Matthew R.
Signorini, Matilde
Vestergaard, Marianne
Waters, Tim
Zu, Ying
High Energy Astrophysical Phenomena
We present the results of the XMM-Newton and NuSTAR observations taken as part of the ongoing, intensive multi-wavelength monitoring program of the Seyfert 1 galaxy Mrk 817 by the AGN Space Telescope and Optical Reverberation Mapping 2 (AGN STORM 2) Project. The campaign revealed an unexpected and transient obscuring outflow, never before seen in this source. Of our four XMM-Newton/NuSTAR epochs, one fortuitously taken during a bright X-ray state has strong narrow absorption lines in the high-resolution grating spectra. From these absorption features, we determine that the obscurer is in fact a multi-phase ionized wind with an outflow velocity of $\sim$5200 km s$^{-1}$, and for the first time find evidence for a lower ionization component with the same velocity observed in absorption features in the contemporaneous HST spectra. This indicates that the UV absorption troughs may be due to dense clumps embedded in diffuse, higher ionization gas responsible for the X-ray absorption lines of the same velocity. We observe variability in the shape of the absorption lines on timescales of hours, placing the variable component at roughly 1000 $R_g$ if attributed to transverse motion along the line of sight. This estimate aligns with independent UV measurements of the distance to the obscurer suggesting an accretion disk wind at the inner broad line region. We estimate that it takes roughly 200 days for the outflow to travel from the disk to our line of sight, consistent with the timescale of the outflow's column density variations throughout the campaign.
title AGN STORM 2: IX. Studying the Dynamics of the Ionized Obscurer in Mrk 817 with High-resolution X-ray Spectroscopy
topic High Energy Astrophysical Phenomena
url https://arxiv.org/abs/2406.17061