Precession-induced Variability in AGN Jets and OJ 287
The combined study of the flaring of active galactic nuclei (AGNs) at radio wavelengths and parsec-scale jet kinematics with Very Long Baseline Interferometry has led to the view that (i) the observed flares are associated with ejections of synchrotron blobs from the core, and (ii) most of the flari...
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2023-01-01
|
| Series: | The Astrophysical Journal |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/1538-4357/accbbc |
| _version_ | 1797694418489180160 |
|---|---|
| author | Silke Britzen Michal Zajaček Gopal-Krishna Christian Fendt Emma Kun Frédéric Jaron Aimo Sillanpää Andreas Eckart |
| author_facet | Silke Britzen Michal Zajaček Gopal-Krishna Christian Fendt Emma Kun Frédéric Jaron Aimo Sillanpää Andreas Eckart |
| author_sort | Silke Britzen |
| collection | DOAJ |
| description | The combined study of the flaring of active galactic nuclei (AGNs) at radio wavelengths and parsec-scale jet kinematics with Very Long Baseline Interferometry has led to the view that (i) the observed flares are associated with ejections of synchrotron blobs from the core, and (ii) most of the flaring follows a one-to-one correlation with the ejection of the component. Recent results have added to the mounting evidence showing that the quasi-regular component injections into the relativistic jet may not be the only cause of the flux variability. We propose that AGN flux variability and changes in jet morphology can both be of deterministic nature, i.e., having a geometric/kinetic origin linked to the time-variable Doppler beaming of the jet emission as its direction changes due to precession (and nutation). The physics of the underlying jet leads to shocks, instabilities, or ejections of plasmoids. The appearance (morphology, flux, etc.) of the jet can, however, be strongly affected and modulated by precession. We demonstrate this modulating power of precession for OJ 287. For the first time, we show that the spectral state of the spectral energy distribution (SED) can be directly related to the jet’s precession phase. We model the SED evolution and reproduce the precession parameters. Further, we apply our precession model to 11 prominent AGNs. We show that for OJ 287 precession seems to dominate the long-term variability (≳1 yr) of the AGN flux, SED spectral state, and jet morphology, while stochastic processes affect the variability on short timescales (≲0.2 yr). |
| first_indexed | 2024-03-12T02:56:41Z |
| format | Article |
| id | doaj.art-f68601296537429cb1cb45ba8282eb37 |
| institution | Directory Open Access Journal |
| issn | 1538-4357 |
| language | English |
| last_indexed | 2024-03-12T02:56:41Z |
| publishDate | 2023-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal |
| spelling | doaj.art-f68601296537429cb1cb45ba8282eb372023-09-03T15:16:06ZengIOP PublishingThe Astrophysical Journal1538-43572023-01-01951210610.3847/1538-4357/accbbcPrecession-induced Variability in AGN Jets and OJ 287Silke Britzen0https://orcid.org/0000-0001-9240-6734Michal Zajaček1https://orcid.org/0000-0001-6450-1187Gopal-Krishna2Christian Fendt3https://orcid.org/0000-0002-3528-7625Emma Kun4https://orcid.org/0000-0003-2769-3591Frédéric Jaron5https://orcid.org/0000-0002-7449-0888Aimo Sillanpää6Andreas Eckart7https://orcid.org/0000-0001-6049-3132Max-Planck-Institut für Radioastronomie , Auf dem Hügel 69, D-53121 Bonn, Germany ; sbritzen@mpifr.deDepartment of Theoretical Physics and Astrophysics, Faculty of Science, Masaryk University Kotlářská 2 , 611 37 Brno, Czech RepublicUM-DAE Centre for Excellence in Basic Sciences , Vidyanagari, Mumbai-400098, IndiaMax Planck Institute for Astronomy , Königstuhl 17, D-69117 Heidelberg, GermanyTheoretical Physics IV: Plasma-Astroparticle Physics, Faculty for Physics & Astronomy, Ruhr University Bochum , D-44780 Bochum, Germany; Ruhr Astroparticle And Plasma Physics Center (RAPP Center) , Ruhr-Universität Bochum D-44780 Bochum, Germany; Astronomical Institute, Faculty for Physics & Astronomy, Ruhr University Bochum , D-44780 Bochum, Germany; Konkoly Observatory, ELKH Research Centre for Astronomy and Earth Sciences , H-1121 Budapest, Konkoly Thege Miklós út 15-17, Hungary; CSFK, MTA Centre of Excellence , Konkoly Thege Miklós út 15-17, HungaryInstitute of Geodesy and Geoinformation, University of Bonn , Nußallee 17, D-53115 Bonn, Germany; Department of Space, Earth and Environment, Chalmers University of Technology , Observatorievägen 90, SE-439 92 Onsala, Sweden; Department of Geodesy and Geoinformation , TU Wien, Wiedner Hauptstraße 8-10, A-1040 Vienna, AustriaTuorla Observatory, University of Turku , Pikkiö, FinlandI.Physikalisches Institut der Universität zu Köln , Zülpicher Str. 77, D-50937 Köln, GermanyThe combined study of the flaring of active galactic nuclei (AGNs) at radio wavelengths and parsec-scale jet kinematics with Very Long Baseline Interferometry has led to the view that (i) the observed flares are associated with ejections of synchrotron blobs from the core, and (ii) most of the flaring follows a one-to-one correlation with the ejection of the component. Recent results have added to the mounting evidence showing that the quasi-regular component injections into the relativistic jet may not be the only cause of the flux variability. We propose that AGN flux variability and changes in jet morphology can both be of deterministic nature, i.e., having a geometric/kinetic origin linked to the time-variable Doppler beaming of the jet emission as its direction changes due to precession (and nutation). The physics of the underlying jet leads to shocks, instabilities, or ejections of plasmoids. The appearance (morphology, flux, etc.) of the jet can, however, be strongly affected and modulated by precession. We demonstrate this modulating power of precession for OJ 287. For the first time, we show that the spectral state of the spectral energy distribution (SED) can be directly related to the jet’s precession phase. We model the SED evolution and reproduce the precession parameters. Further, we apply our precession model to 11 prominent AGNs. We show that for OJ 287 precession seems to dominate the long-term variability (≳1 yr) of the AGN flux, SED spectral state, and jet morphology, while stochastic processes affect the variability on short timescales (≲0.2 yr).https://doi.org/10.3847/1538-4357/accbbcActive galactic nucleiBlazarsRelativistic jetsGalaxy mergersRadio interferometryGravitational waves |
| spellingShingle | Silke Britzen Michal Zajaček Gopal-Krishna Christian Fendt Emma Kun Frédéric Jaron Aimo Sillanpää Andreas Eckart Precession-induced Variability in AGN Jets and OJ 287 The Astrophysical Journal Active galactic nuclei Blazars Relativistic jets Galaxy mergers Radio interferometry Gravitational waves |
| title | Precession-induced Variability in AGN Jets and OJ 287 |
| title_full | Precession-induced Variability in AGN Jets and OJ 287 |
| title_fullStr | Precession-induced Variability in AGN Jets and OJ 287 |
| title_full_unstemmed | Precession-induced Variability in AGN Jets and OJ 287 |
| title_short | Precession-induced Variability in AGN Jets and OJ 287 |
| title_sort | precession induced variability in agn jets and oj 287 |
| topic | Active galactic nuclei Blazars Relativistic jets Galaxy mergers Radio interferometry Gravitational waves |
| url | https://doi.org/10.3847/1538-4357/accbbc |
| work_keys_str_mv | AT silkebritzen precessioninducedvariabilityinagnjetsandoj287 AT michalzajacek precessioninducedvariabilityinagnjetsandoj287 AT gopalkrishna precessioninducedvariabilityinagnjetsandoj287 AT christianfendt precessioninducedvariabilityinagnjetsandoj287 AT emmakun precessioninducedvariabilityinagnjetsandoj287 AT fredericjaron precessioninducedvariabilityinagnjetsandoj287 AT aimosillanpaa precessioninducedvariabilityinagnjetsandoj287 AT andreaseckart precessioninducedvariabilityinagnjetsandoj287 |