AGN STORM 2. V. Anomalous Behavior of the C iv Light Curve of Mrk 817
An intensive reverberation mapping campaign of the Seyfert 1 galaxy Mrk 817 using the Cosmic Origins Spectrograph on the Hubble Space Telescope revealed significant variations in the response of broad UV emission lines to fluctuations in the continuum emission. The response of the prominent UV emiss...
Saved in:
| Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2024-01-01
|
| Series: | The Astrophysical Journal |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/1538-4357/ad1be4 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849409132999737344 |
|---|---|
| author | Y. Homayouni Gerard A. Kriss Gisella De Rosa Rachel Plesha Edward M. Cackett Michael R. Goad Kirk T. Korista Keith Horne Travis Fischer Tim Waters Aaron J. Barth Erin A. Kara Hermine Landt Nahum Arav Benjamin D. Boizelle Misty C. Bentz Michael S. Brotherton Doron Chelouche Elena Dalla Bontà Maryam Dehghanian Pu Du Gary J. Ferland Carina Fian Jonathan Gelbord Catherine J. Grier Patrick B. Hall Chen Hu Dragana Ilić Michael D. Joner Jelle Kaastra Shai Kaspi Andjelka B. Kovačević Daniel Kynoch Yan-Rong Li Missagh Mehdipour Jake A. Miller Jake Mitchell John Montano Hagai Netzer J. M. M. Neustadt Ethan Partington Luka Č. Popović Daniel Proga Thaisa Storchi-Bergmann David Sanmartim Matthew R. Siebert Tommaso Treu Marianne Vestergaard Jian-Min Wang Martin J. Ward Fatima Zaidouni Ying Zu |
| author_facet | Y. Homayouni Gerard A. Kriss Gisella De Rosa Rachel Plesha Edward M. Cackett Michael R. Goad Kirk T. Korista Keith Horne Travis Fischer Tim Waters Aaron J. Barth Erin A. Kara Hermine Landt Nahum Arav Benjamin D. Boizelle Misty C. Bentz Michael S. Brotherton Doron Chelouche Elena Dalla Bontà Maryam Dehghanian Pu Du Gary J. Ferland Carina Fian Jonathan Gelbord Catherine J. Grier Patrick B. Hall Chen Hu Dragana Ilić Michael D. Joner Jelle Kaastra Shai Kaspi Andjelka B. Kovačević Daniel Kynoch Yan-Rong Li Missagh Mehdipour Jake A. Miller Jake Mitchell John Montano Hagai Netzer J. M. M. Neustadt Ethan Partington Luka Č. Popović Daniel Proga Thaisa Storchi-Bergmann David Sanmartim Matthew R. Siebert Tommaso Treu Marianne Vestergaard Jian-Min Wang Martin J. Ward Fatima Zaidouni Ying Zu |
| author_sort | Y. Homayouni |
| collection | DOAJ |
| description | An intensive reverberation mapping campaign of the Seyfert 1 galaxy Mrk 817 using the Cosmic Origins Spectrograph on the Hubble Space Telescope revealed significant variations in the response of broad UV emission lines to fluctuations in the continuum emission. The response of the prominent UV emission lines changes over an ∼60 day duration, resulting in distinctly different time lags in the various segments of the light curve over the 14 month observing campaign. One-dimensional echo-mapping models fit these variations if a slowly varying background is included for each emission line. These variations are more evident in the C iv light curve, which is the line least affected by intrinsic absorption in Mrk 817 and least blended with neighboring emission lines. We identify five temporal windows with a distinct emission-line response, and measure their corresponding time delays, which range from 2 to 13 days. These temporal windows are plausibly linked to changes in the UV and X-ray obscuration occurring during these same intervals. The shortest time lags occur during periods with diminishing obscuration, whereas the longest lags occur during periods with rising obscuration. We propose that the obscuring outflow shields the broad UV lines from the ionizing continuum. The resulting change in the spectral energy distribution of the ionizing continuum, as seen by clouds at a range of distances from the nucleus, is responsible for the changes in the line response. |
| format | Article |
| id | doaj-art-316614fb5a9e43ee843eceed4152da03 |
| institution | Kabale University |
| issn | 1538-4357 |
| language | English |
| publishDate | 2024-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal |
| spelling | doaj-art-316614fb5a9e43ee843eceed4152da032025-08-20T03:35:36ZengIOP PublishingThe Astrophysical Journal1538-43572024-01-01963212310.3847/1538-4357/ad1be4AGN STORM 2. V. Anomalous Behavior of the C iv Light Curve of Mrk 817Y. Homayouni0https://orcid.org/0000-0002-0957-7151Gerard A. Kriss1https://orcid.org/0000-0002-2180-8266Gisella De Rosa2https://orcid.org/0000-0003-3242-7052Rachel Plesha3https://orcid.org/0000-0002-2509-3878Edward M. Cackett4https://orcid.org/0000-0002-8294-9281Michael R. Goad5https://orcid.org/0000-0002-2908-7360Kirk T. Korista6https://orcid.org/0000-0003-0944-1008Keith Horne7https://orcid.org/0000-0003-1728-0304Travis Fischer8https://orcid.org/0000-0002-3365-8875Tim Waters9https://orcid.org/0000-0002-5205-9472Aaron J. Barth10https://orcid.org/0000-0002-3026-0562Erin A. Kara11https://orcid.org/0000-0003-0172-0854Hermine Landt12https://orcid.org/0000-0001-8391-6900Nahum Arav13https://orcid.org/0000-0003-2991-4618Benjamin D. Boizelle14https://orcid.org/0000-0001-6301-570XMisty C. Bentz15https://orcid.org/0000-0002-2816-5398Michael S. Brotherton16https://orcid.org/0000-0002-1207-0909Doron Chelouche17https://orcid.org/0000-0002-4830-7787Elena Dalla Bontà18https://orcid.org/0000-0001-9931-8681Maryam Dehghanian19https://orcid.org/0000-0002-0964-7500Pu Du20https://orcid.org/0000-0002-5830-3544Gary J. Ferland21https://orcid.org/0000-0003-4503-6333Carina Fian22https://orcid.org/0000-0002-2306-9372Jonathan Gelbord23https://orcid.org/0000-0001-9092-8619Catherine J. Grier24https://orcid.org/0000-0001-9920-6057Patrick B. Hall25https://orcid.org/0000-0002-1763-5825Chen Hu26Dragana Ilić27https://orcid.org/0000-0002-1134-4015Michael D. Joner28https://orcid.org/0000-0003-0634-8449Jelle Kaastra29https://orcid.org/0000-0001-5540-2822Shai Kaspi30https://orcid.org/0000-0002-9925-534XAndjelka B. Kovačević31https://orcid.org/0000-0001-5139-1978Daniel Kynoch32https://orcid.org/0000-0001-8638-3687Yan-Rong Li33https://orcid.org/0000-0001-5841-9179Missagh Mehdipour34https://orcid.org/0000-0002-4992-4664Jake A. Miller35https://orcid.org/0000-0001-8475-8027Jake Mitchell36https://orcid.org/0000-0002-5493-1420John Montano37https://orcid.org/0000-0001-5639-5484Hagai Netzer38https://orcid.org/0000-0002-6766-0260J. M. M. Neustadt39https://orcid.org/0000-0001-7351-2531Ethan Partington40https://orcid.org/0000-0003-1183-1574Luka Č. Popović41https://orcid.org/0000-0003-2398-7664Daniel Proga42https://orcid.org/0000-0002-6336-5125Thaisa Storchi-Bergmann43https://orcid.org/0000-0003-1772-0023David Sanmartim44https://orcid.org/0000-0002-9238-9521Matthew R. Siebert45https://orcid.org/0000-0003-2445-3891Tommaso Treu46https://orcid.org/0000-0002-8460-0390Marianne Vestergaard47https://orcid.org/0000-0001-9191-9837Jian-Min Wang48https://orcid.org/0000-0001-9449-9268Martin J. Ward49https://orcid.org/0000-0003-1810-0889Fatima Zaidouni50https://orcid.org/0000-0003-0931-0868Ying Zu51https://orcid.org/0000-0001-6966-6925Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA; Department of Astronomy and Astrophysics, The Pennsylvania State University , 525 Davey Laboratory, University Park, PA 16802, USA; Institute for Gravitation and the Cosmos, The Pennsylvania State University , University Park, PA 16802, USASpace Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USASpace Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USASpace Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USADepartment of Physics and Astronomy, Wayne State University , 666 W. Hancock Street, Detroit, MI 48201, USASchool of Physics and Astronomy, University of Leicester , University Road, Leicester LE1 7RH, UKDepartment of Physics, Western Michigan University , 1120 Everett Tower, Kalamazoo, MI 49008-5252, USASUPA School of Physics and Astronomy , North Haugh, St. Andrews KY16 9SS, Scotland, UKAURA for ESA, Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USADepartment of Physics & Astronomy, University of Nevada, Las Vegas , 4505 S. Maryland Parkway, Las Vegas, NV 89154-4002, USADepartment of Physics and Astronomy, 4129 Frederick Reines Hall, University of California , Irvine, CA 92697-4575, USAMIT Kavli Institute for Astrophysics and Space Research , Massachusetts Institute of Technology, Cambridge, MA 02139, USACentre for Extragalactic Astronomy, Department of Physics, Durham University , South Road, Durham DH1 3LE, UKDepartment of Physics , Virginia Tech, Blacksburg, VA 24061, USADepartment of Physics and Astronomy, N284 ESC, Brigham Young University , Provo, UT 84602, USADepartment of Physics and Astronomy, Georgia State University , 25 Park Place, Suite 605, Atlanta, GA 30303, USADepartment of Physics and Astronomy, University of Wyoming , Laramie, WY 82071, USADepartment of Physics, Faculty of Natural Sciences, University of Haifa , Haifa 3498838, Israel; Haifa Research Center for Theoretical Physics and Astrophysics, University of Haifa , Haifa 3498838, IsraelDipartimento di Fisica e Astronomia “G. Galilei,” Università di Padova , Vicolo dell’Osservatorio 3, I-35122 Padova, Italy; INAF-Osservatorio Astronomico di Padova , Vicolo dell’Osservatorio 5, I-35122 Padova, ItalyDepartment of Physics and Astronomy, The University of Kentucky , Lexington, KY 40506, USAKey Laboratory for Particle Astrophysics, Institute of High Energy Physics , Chinese Academy of Sciences, 19B Yuquan Road, Beijing 100049, People's Republic of ChinaDepartment of Physics and Astronomy, The University of Kentucky , Lexington, KY 40506, USAHaifa Research Center for Theoretical Physics and Astrophysics, University of Haifa , Haifa 3498838, Israel; School of Physics and Astronomy and Wise observatory, Tel Aviv University , Tel Aviv 6997801, IsraelSpectral Sciences Inc. , 4 Fourth Avenue, Burlington, MA 01803, USADepartment of Astronomy, University of Wisconsin-Madison , Madison, WI 53706, USADepartment of Physics and Astronomy, York University , Toronto, ON M3J 1P3, CanadaKey Laboratory for Particle Astrophysics, Institute of High Energy Physics , Chinese Academy of Sciences, 19B Yuquan Road, Beijing 100049, People's Republic of ChinaUniversity of Belgrade—Faculty of Mathematics , Department of Astronomy, Studentski trg 16, Belgrade, Serbia; Hamburger Sternwarte, Universität Hamburg , Gojenbergsweg 112, D-21029 Hamburg, GermanyDepartment of Physics and Astronomy, N284 ESC, Brigham Young University , Provo, UT 84602, USASRON Netherlands Institute for Space Research , Niels Bohrweg 4, 2333 CA Leiden, The Netherlands; Leiden Observatory, Leiden University , P.O. Box 9513, 2300 RA Leiden, The NetherlandsSchool of Physics and Astronomy and Wise observatory, Tel Aviv University , Tel Aviv 6997801, IsraelUniversity of Belgrade—Faculty of Mathematics , Department of Astronomy, Studentski trg 16, Belgrade, SerbiaSchool of Physics and Astronomy, University of Southampton , Highfield, Southampton SO17 1BJ, UK; Astronomical Institute of the Czech Academy of Sciences , Boční II 1401, 141 00 Prague, CzechiaKey Laboratory for Particle Astrophysics, Institute of High Energy Physics , Chinese Academy of Sciences, 19B Yuquan Road, Beijing 100049, People's Republic of ChinaSpace Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USADepartment of Physics and Astronomy, Wayne State University , 666 W. Hancock Street, Detroit, MI 48201, USACentre for Extragalactic Astronomy, Department of Physics, Durham University , South Road, Durham DH1 3LE, UKDepartment of Physics and Astronomy, 4129 Frederick Reines Hall, University of California , Irvine, CA 92697-4575, USASchool of Physics and Astronomy and Wise observatory, Tel Aviv University , Tel Aviv 6997801, IsraelDepartment of Astronomy, The Ohio State University , 140 West 18th Avenue, Columbus, OH 43210, USADepartment of Physics and Astronomy, Wayne State University , 666 W. Hancock Street, Detroit, MI 48201, USAUniversity of Belgrade—Faculty of Mathematics , Department of Astronomy, Studentski trg 16, Belgrade, Serbia; Astronomical Observatory , Volgina 7, 11060 Belgrade, SerbiaDepartment of Physics & Astronomy, University of Nevada, Las Vegas , 4505 S. Maryland Parkway, Las Vegas, NV 89154-4002, USADepartamento de Astronomia—IF, Universidade Federal do Rio Grande do Sul , CP 150501, 91501-970 Porto Alegre, RS, BrazilRubin Observatory Project Office , 950 N. Cherry Avenue, Tucson, AZ 85719, USADepartment of Astronomy and Astrophysics, University of California , Santa Cruz, CA 92064, USADepartment of Physics and Astronomy, University of California , Los Angeles, CA 90095, USASteward Observatory, University of Arizona , 933 North Cherry Avenue, Tucson, AZ 85721, USA; DARK, The Niels Bohr Institute, University of Copenhagen , Jagtvej 155, DK-2200 Copenhagen, DenmarkKey Laboratory for Particle Astrophysics, Institute of High Energy Physics , Chinese Academy of Sciences, 19B Yuquan Road, Beijing 100049, People's Republic of China; School of Astronomy and Space Sciences, University of Chinese Academy of Sciences , 19A Yuquan Road, Beijing 100049, People's Republic of China; National Astronomical Observatories of China , 20A Datun Road, Beijing 100020, People's Republic of ChinaCentre for Extragalactic Astronomy, Department of Physics, Durham University , South Road, Durham DH1 3LE, UKMIT Kavli Institute for Astrophysics and Space Research , Massachusetts Institute of Technology, Cambridge, MA 02139, USADepartment of Astronomy, School of Physics and Astronomy, Shanghai Jiao Tong University , 800 Dongchuan Road, Shanghai 200240, People's Republic of China; Shanghai Key Laboratory for Particle Physics and Cosmology, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of ChinaAn intensive reverberation mapping campaign of the Seyfert 1 galaxy Mrk 817 using the Cosmic Origins Spectrograph on the Hubble Space Telescope revealed significant variations in the response of broad UV emission lines to fluctuations in the continuum emission. The response of the prominent UV emission lines changes over an ∼60 day duration, resulting in distinctly different time lags in the various segments of the light curve over the 14 month observing campaign. One-dimensional echo-mapping models fit these variations if a slowly varying background is included for each emission line. These variations are more evident in the C iv light curve, which is the line least affected by intrinsic absorption in Mrk 817 and least blended with neighboring emission lines. We identify five temporal windows with a distinct emission-line response, and measure their corresponding time delays, which range from 2 to 13 days. These temporal windows are plausibly linked to changes in the UV and X-ray obscuration occurring during these same intervals. The shortest time lags occur during periods with diminishing obscuration, whereas the longest lags occur during periods with rising obscuration. We propose that the obscuring outflow shields the broad UV lines from the ionizing continuum. The resulting change in the spectral energy distribution of the ionizing continuum, as seen by clouds at a range of distances from the nucleus, is responsible for the changes in the line response.https://doi.org/10.3847/1538-4357/ad1be4Active galaxiesActive galactic nucleiSeyfert galaxiesGalaxy nuclei |
| spellingShingle | Y. Homayouni Gerard A. Kriss Gisella De Rosa Rachel Plesha Edward M. Cackett Michael R. Goad Kirk T. Korista Keith Horne Travis Fischer Tim Waters Aaron J. Barth Erin A. Kara Hermine Landt Nahum Arav Benjamin D. Boizelle Misty C. Bentz Michael S. Brotherton Doron Chelouche Elena Dalla Bontà Maryam Dehghanian Pu Du Gary J. Ferland Carina Fian Jonathan Gelbord Catherine J. Grier Patrick B. Hall Chen Hu Dragana Ilić Michael D. Joner Jelle Kaastra Shai Kaspi Andjelka B. Kovačević Daniel Kynoch Yan-Rong Li Missagh Mehdipour Jake A. Miller Jake Mitchell John Montano Hagai Netzer J. M. M. Neustadt Ethan Partington Luka Č. Popović Daniel Proga Thaisa Storchi-Bergmann David Sanmartim Matthew R. Siebert Tommaso Treu Marianne Vestergaard Jian-Min Wang Martin J. Ward Fatima Zaidouni Ying Zu AGN STORM 2. V. Anomalous Behavior of the C iv Light Curve of Mrk 817 The Astrophysical Journal Active galaxies Active galactic nuclei Seyfert galaxies Galaxy nuclei |
| title | AGN STORM 2. V. Anomalous Behavior of the C iv Light Curve of Mrk 817 |
| title_full | AGN STORM 2. V. Anomalous Behavior of the C iv Light Curve of Mrk 817 |
| title_fullStr | AGN STORM 2. V. Anomalous Behavior of the C iv Light Curve of Mrk 817 |
| title_full_unstemmed | AGN STORM 2. V. Anomalous Behavior of the C iv Light Curve of Mrk 817 |
| title_short | AGN STORM 2. V. Anomalous Behavior of the C iv Light Curve of Mrk 817 |
| title_sort | agn storm 2 v anomalous behavior of the c iv light curve of mrk 817 |
| topic | Active galaxies Active galactic nuclei Seyfert galaxies Galaxy nuclei |
| url | https://doi.org/10.3847/1538-4357/ad1be4 |
| work_keys_str_mv | AT yhomayouni agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT gerardakriss agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT giselladerosa agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT rachelplesha agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT edwardmcackett agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT michaelrgoad agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT kirktkorista agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT keithhorne agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT travisfischer agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT timwaters agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT aaronjbarth agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT erinakara agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT herminelandt agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT nahumarav agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT benjamindboizelle agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT mistycbentz agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT michaelsbrotherton agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT doronchelouche agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT elenadallabonta agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT maryamdehghanian agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT pudu agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT garyjferland agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT carinafian agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT jonathangelbord agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT catherinejgrier agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT patrickbhall agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT chenhu agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT draganailic agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT michaeldjoner agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT jellekaastra agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT shaikaspi agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT andjelkabkovacevic agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT danielkynoch agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT yanrongli agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT missaghmehdipour agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT jakeamiller agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT jakemitchell agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT johnmontano agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT hagainetzer agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT jmmneustadt agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT ethanpartington agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT lukacpopovic agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT danielproga agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT thaisastorchibergmann agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT davidsanmartim agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT matthewrsiebert agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT tommasotreu agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT mariannevestergaard agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT jianminwang agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT martinjward agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT fatimazaidouni agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 AT yingzu agnstorm2vanomalousbehaviorofthecivlightcurveofmrk817 |