AT 2019avd: A novel addition to the diverse population of nuclear transients
We report on SRG/eROSITA, ZTF, ASAS-SN, Las Cumbres, NEOWISE-R, and Swift XRT/UVOT observations of the unique ongoing event AT 2019avd, located in the nucleus of a previously inactive galaxy at z = 0.029. eROSITA first observed AT 2019avd on 2020-04-28 during its first all sky survey, when it was de...
| Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |
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| Format: | Journal Article |
| Language: | English |
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EDP SCIENCES S A
2021
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1051/0004-6361/202039681 http://hdl.handle.net/20.500.11937/90309 |
| _version_ | 1848765366853959680 |
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| author | Malyali, A. Rau, A. Merloni, A. Nandra, K. Buchner, J. Liu, Z. Gezari, S. Sollerman, J. Shappee, B. Trakhtenbrot, B. Arcavi, I. Ricci, C. Van Velzen, S. Goobar, A. Frederick, S. Kawka, A. Tartaglia, L. Burke, J. Hiramatsu, D. Schramm, M. Van Der Boom, D. Anderson, Gemma Miller-Jones, James Bellm, E. Drake, A. Duev, D. Fremling, C. Graham, M. Masci, F. Rusholme, B. Soumagnac, M. Walters, R. |
| author_facet | Malyali, A. Rau, A. Merloni, A. Nandra, K. Buchner, J. Liu, Z. Gezari, S. Sollerman, J. Shappee, B. Trakhtenbrot, B. Arcavi, I. Ricci, C. Van Velzen, S. Goobar, A. Frederick, S. Kawka, A. Tartaglia, L. Burke, J. Hiramatsu, D. Schramm, M. Van Der Boom, D. Anderson, Gemma Miller-Jones, James Bellm, E. Drake, A. Duev, D. Fremling, C. Graham, M. Masci, F. Rusholme, B. Soumagnac, M. Walters, R. |
| author_sort | Malyali, A. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | We report on SRG/eROSITA, ZTF, ASAS-SN, Las Cumbres, NEOWISE-R, and Swift XRT/UVOT observations of the unique ongoing event AT 2019avd, located in the nucleus of a previously inactive galaxy at z = 0.029. eROSITA first observed AT 2019avd on 2020-04-28 during its first all sky survey, when it was detected as an ultra-soft X-ray source (kT 85 eV) that was a 90 times brighter in the 0.2-2 keV band than a previous 3σ upper flux detection limit (with no archival X-ray detection at this position). The ZTF optical light curve in the 450 days preceding the eROSITA detection is double peaked, and the eROSITA detection coincides with the rise of the second peak. Follow-up optical spectroscopy shows the emergence of a Bowen fluorescence feature and high-ionisation coronal lines ([Fea» X] 6375 Å, [Fea» XIV] 5303 Å), along with persistent broad Balmer emission lines (FWHM 1400 km s-1). Whilst the X-ray properties make AT 2019avd a promising tidal disruption event (TDE) candidate, the optical properties are atypical for optically selected TDEs. We discuss potential alternative origins that could explain the observed properties of AT 2019avd, such as a stellar binary TDE candidate, or a TDE involving a super massive black hole binary. |
| first_indexed | 2025-11-14T11:34:07Z |
| format | Journal Article |
| id | curtin-20.500.11937-90309 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T11:34:07Z |
| publishDate | 2021 |
| publisher | EDP SCIENCES S A |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-903092023-02-10T03:32:59Z AT 2019avd: A novel addition to the diverse population of nuclear transients Malyali, A. Rau, A. Merloni, A. Nandra, K. Buchner, J. Liu, Z. Gezari, S. Sollerman, J. Shappee, B. Trakhtenbrot, B. Arcavi, I. Ricci, C. Van Velzen, S. Goobar, A. Frederick, S. Kawka, A. Tartaglia, L. Burke, J. Hiramatsu, D. Schramm, M. Van Der Boom, D. Anderson, Gemma Miller-Jones, James Bellm, E. Drake, A. Duev, D. Fremling, C. Graham, M. Masci, F. Rusholme, B. Soumagnac, M. Walters, R. Science & Technology Physical Sciences Astronomy & Astrophysics X-rays: galaxies accretion accretion disks galaxies: nuclei TIDAL DISRUPTION EVENT ACTIVE GALACTIC NUCLEI BROAD-LINE REGION SUPERMASSIVE BLACK-HOLE INFRARED-SURVEY-EXPLORER CHANGING-LOOK AGN X-RAY OUTBURST HOST GALAXIES MIDINFRARED SELECTION EMISSION-LINES We report on SRG/eROSITA, ZTF, ASAS-SN, Las Cumbres, NEOWISE-R, and Swift XRT/UVOT observations of the unique ongoing event AT 2019avd, located in the nucleus of a previously inactive galaxy at z = 0.029. eROSITA first observed AT 2019avd on 2020-04-28 during its first all sky survey, when it was detected as an ultra-soft X-ray source (kT 85 eV) that was a 90 times brighter in the 0.2-2 keV band than a previous 3σ upper flux detection limit (with no archival X-ray detection at this position). The ZTF optical light curve in the 450 days preceding the eROSITA detection is double peaked, and the eROSITA detection coincides with the rise of the second peak. Follow-up optical spectroscopy shows the emergence of a Bowen fluorescence feature and high-ionisation coronal lines ([Fea» X] 6375 Å, [Fea» XIV] 5303 Å), along with persistent broad Balmer emission lines (FWHM 1400 km s-1). Whilst the X-ray properties make AT 2019avd a promising tidal disruption event (TDE) candidate, the optical properties are atypical for optically selected TDEs. We discuss potential alternative origins that could explain the observed properties of AT 2019avd, such as a stellar binary TDE candidate, or a TDE involving a super massive black hole binary. 2021 Journal Article http://hdl.handle.net/20.500.11937/90309 10.1051/0004-6361/202039681 English http://dx.doi.org/10.1051/0004-6361/202039681 http://purl.org/au-research/grants/arc/DE180100346 http://purl.org/au-research/grants/arc/DP200102471 http://creativecommons.org/licenses/by/4.0 EDP SCIENCES S A fulltext |
| spellingShingle | Science & Technology Physical Sciences Astronomy & Astrophysics X-rays: galaxies accretion accretion disks galaxies: nuclei TIDAL DISRUPTION EVENT ACTIVE GALACTIC NUCLEI BROAD-LINE REGION SUPERMASSIVE BLACK-HOLE INFRARED-SURVEY-EXPLORER CHANGING-LOOK AGN X-RAY OUTBURST HOST GALAXIES MIDINFRARED SELECTION EMISSION-LINES Malyali, A. Rau, A. Merloni, A. Nandra, K. Buchner, J. Liu, Z. Gezari, S. Sollerman, J. Shappee, B. Trakhtenbrot, B. Arcavi, I. Ricci, C. Van Velzen, S. Goobar, A. Frederick, S. Kawka, A. Tartaglia, L. Burke, J. Hiramatsu, D. Schramm, M. Van Der Boom, D. Anderson, Gemma Miller-Jones, James Bellm, E. Drake, A. Duev, D. Fremling, C. Graham, M. Masci, F. Rusholme, B. Soumagnac, M. Walters, R. AT 2019avd: A novel addition to the diverse population of nuclear transients |
| title | AT 2019avd: A novel addition to the diverse population of nuclear transients |
| title_full | AT 2019avd: A novel addition to the diverse population of nuclear transients |
| title_fullStr | AT 2019avd: A novel addition to the diverse population of nuclear transients |
| title_full_unstemmed | AT 2019avd: A novel addition to the diverse population of nuclear transients |
| title_short | AT 2019avd: A novel addition to the diverse population of nuclear transients |
| title_sort | at 2019avd: a novel addition to the diverse population of nuclear transients |
| topic | Science & Technology Physical Sciences Astronomy & Astrophysics X-rays: galaxies accretion accretion disks galaxies: nuclei TIDAL DISRUPTION EVENT ACTIVE GALACTIC NUCLEI BROAD-LINE REGION SUPERMASSIVE BLACK-HOLE INFRARED-SURVEY-EXPLORER CHANGING-LOOK AGN X-RAY OUTBURST HOST GALAXIES MIDINFRARED SELECTION EMISSION-LINES |
| url | http://dx.doi.org/10.1051/0004-6361/202039681 http://dx.doi.org/10.1051/0004-6361/202039681 http://dx.doi.org/10.1051/0004-6361/202039681 http://hdl.handle.net/20.500.11937/90309 |