Probing the Large Faraday Rotation Measure Environment of Compact Active Galactic Nuclei
Knowing how the ambient medium in the vicinity of active galactic nuclei (AGNs) is shaped is crucial to understanding generally the evolution of such cosmic giants as well as AGN jet formation and launching. Thanks to the new broadband capability now available at the Jansky Very Large Array (JVLA),...
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| Format: | Article |
| Language: | English |
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MDPI AG
2018-03-01
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| Series: | Galaxies |
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| Online Access: | http://www.mdpi.com/2075-4434/6/2/40 |
| _version_ | 1817996542098800640 |
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| author | Alice Pasetto Carlos Carrasco-González Shane O’Sullivan Aritra Basu Gabriele Bruni Alex Kraus Salvador Curiel Karl-Heinz Mack |
| author_facet | Alice Pasetto Carlos Carrasco-González Shane O’Sullivan Aritra Basu Gabriele Bruni Alex Kraus Salvador Curiel Karl-Heinz Mack |
| author_sort | Alice Pasetto |
| collection | DOAJ |
| description | Knowing how the ambient medium in the vicinity of active galactic nuclei (AGNs) is shaped is crucial to understanding generally the evolution of such cosmic giants as well as AGN jet formation and launching. Thanks to the new broadband capability now available at the Jansky Very Large Array (JVLA), we can study changes in polarization properties, fractional polarization, and polarization angles, together with the total intensity spectra of a sample of 14 AGNs, within a frequency range from 1 to 12 GHz. Depolarization modeling has been performed by means of so-called “qu-fitting” to the polarized data, and a synchrotron self absorption model has been used for fitting to the total intensity data. We found complex behavior both in the polarization spectra and in the total intensity spectra, and several Faraday components with a large rotation measure (RM) and several synchrotron components were needed to represent these spectra. Here, results for three targets are shown. This new method of analyzing broadband polarization data through qu-fitting successfully maps the complex surroundings of unresolved objects. |
| first_indexed | 2024-04-14T02:23:44Z |
| format | Article |
| id | doaj.art-f887e601de5944c8abb232fdbe392f9c |
| institution | Directory Open Access Journal |
| issn | 2075-4434 |
| language | English |
| last_indexed | 2024-04-14T02:23:44Z |
| publishDate | 2018-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Galaxies |
| spelling | doaj.art-f887e601de5944c8abb232fdbe392f9c2022-12-22T02:17:58ZengMDPI AGGalaxies2075-44342018-03-01624010.3390/galaxies6020040galaxies6020040Probing the Large Faraday Rotation Measure Environment of Compact Active Galactic NucleiAlice Pasetto0Carlos Carrasco-González1Shane O’Sullivan2Aritra Basu3Gabriele Bruni4Alex Kraus5Salvador Curiel6Karl-Heinz Mack7Instituto de Radioastronomía y Astrofísica (IRyA-UNAM), Antigua Carretera a Pátzcuaro, Morelia, Michoacán 58341, MexicoInstituto de Radioastronomía y Astrofísica (IRyA-UNAM), Antigua Carretera a Pátzcuaro, Morelia, Michoacán 58341, MexicoHamburger Sternwarte, Universität Hamburg, Gojenbergsweg 112, 21029 Hamburg, GermanyMax-Planck Institut für Radioastronomie (MPIfR), Auf dem Hügel 69, D-53121 Bonn, GermanyIstituto di Astrofisica e Planetologia Spaziali (IAPS-INAF), via Fosso del Cavaliere 100, I-00133 Rome, ItalyMax-Planck Institut für Radioastronomie (MPIfR), Auf dem Hügel 69, D-53121 Bonn, GermanyInstituto de Astronomía, UNAM, Apartado Postal 70-264, Mexico 04510 , MexicoIstituto di Radioastronomia (IRA-INAF), Via Gobetti 101, I-40129 Bologna, ItalyKnowing how the ambient medium in the vicinity of active galactic nuclei (AGNs) is shaped is crucial to understanding generally the evolution of such cosmic giants as well as AGN jet formation and launching. Thanks to the new broadband capability now available at the Jansky Very Large Array (JVLA), we can study changes in polarization properties, fractional polarization, and polarization angles, together with the total intensity spectra of a sample of 14 AGNs, within a frequency range from 1 to 12 GHz. Depolarization modeling has been performed by means of so-called “qu-fitting” to the polarized data, and a synchrotron self absorption model has been used for fitting to the total intensity data. We found complex behavior both in the polarization spectra and in the total intensity spectra, and several Faraday components with a large rotation measure (RM) and several synchrotron components were needed to represent these spectra. Here, results for three targets are shown. This new method of analyzing broadband polarization data through qu-fitting successfully maps the complex surroundings of unresolved objects.http://www.mdpi.com/2075-4434/6/2/40polarizationspectro-polarimetric studyqu-fittingAGN surroundings |
| spellingShingle | Alice Pasetto Carlos Carrasco-González Shane O’Sullivan Aritra Basu Gabriele Bruni Alex Kraus Salvador Curiel Karl-Heinz Mack Probing the Large Faraday Rotation Measure Environment of Compact Active Galactic Nuclei Galaxies polarization spectro-polarimetric study qu-fitting AGN surroundings |
| title | Probing the Large Faraday Rotation Measure Environment of Compact Active Galactic Nuclei |
| title_full | Probing the Large Faraday Rotation Measure Environment of Compact Active Galactic Nuclei |
| title_fullStr | Probing the Large Faraday Rotation Measure Environment of Compact Active Galactic Nuclei |
| title_full_unstemmed | Probing the Large Faraday Rotation Measure Environment of Compact Active Galactic Nuclei |
| title_short | Probing the Large Faraday Rotation Measure Environment of Compact Active Galactic Nuclei |
| title_sort | probing the large faraday rotation measure environment of compact active galactic nuclei |
| topic | polarization spectro-polarimetric study qu-fitting AGN surroundings |
| url | http://www.mdpi.com/2075-4434/6/2/40 |
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