A1 Vertaisarvioitu alkuperäisartikkeli tieteellisessä lehdessä
The case of AT2022wtn: a tidal disruption event in an interacting galaxy
Tekijät: Onori, F.; Nicholl, M.; Ramsden, P.; McGee, S.; Roy, R.; Li, W.; Arcavi, I; Anderson, J. P.; Brocato, E.; Bronikowski, M.; Cenko, S. B.; Chambers, K.; Chen, T. W.; Clark, P.; Concepcion, E.; Farah, J.; Flammini, D.; González-Gaitán, S.; Gromadzki, M.; Gutiérrez, C. P.; Hammerstein, E.; Hinds, K. R.; Inserra, C.; Kankare, E.; Kumar, A.; Makrygianni, L.; Mattila, S.; Matilainen, K. K.; Mueller-Bravo, T. E.; Petrushevska, T.; Pignata, G.; Piranomonte, S.; Reynolds, T. M.; Stein, R.; Wang, Y.; Wevers, T.; Yao, Y.; Young, D. R.
Kustantaja: OXFORD UNIV PRESS
Kustannuspaikka: OXFORD
Julkaisuvuosi: 2025
Journal: Monthly Notices of the Royal Astronomical Society
Tietokannassa oleva lehden nimi: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Lehden akronyymi: MON NOT R ASTRON SOC
Vuosikerta: 540
Numero: 1
Aloitussivu: 498
Lopetussivu: 520
Sivujen määrä: 23
ISSN: 0035-8711
eISSN: 1365-2966
DOI: https://doi.org/10.1093/mnras/staf746
Verkko-osoite: https://academic.oup.com/mnras/article/540/1/498/8127236
Rinnakkaistallenteen osoite: https://research.utu.fi/converis/portal/detail/Publication/498697665
We present the results from our multiwavelength monitoring campaign of the transient AT 2022wtn, discovered by the Zwicky Transient Facility in the nucleus of SDSS J232323.79 + 104107.7, the less-massive galaxy in an active merging pair with a mass ratio of similar to 10:1. AT 2022wtn shows spectroscopic and photometric properties consistent with a X-ray faint N-strong TDE-H + He with a number of peculiarities. Specifically, a 30-d long plateau at maximum luminosity, a corresponding dip in temperature and the development of a double-horned N III + He II line profile. Strong and time-evolving velocity offsets in the tidal disruption event (TDE) broad emission lines and the detection of a transient radio emission, indicate the presence of outflows. Overall, the observed properties are consistent with the full disruption of a low-mass star by a similar to 106M(circle dot) supermassive black hole followed by an efficient disc formation and the launch of a quasi-spherical reprocessing envelope of fast expanding outflowing material. The observed differences between the He II and the Hydrogen and N III lines can be explained either with a spatial separation of the lines emitting region or with a late-time reveal of shocks from the returning debris streams, as the photosphere recedes. Finally, we present an extensive analysis of the hosting environment and discuss the implications for the discovery of two TDEs in interacting galaxy pairs, finding indication for an over-representation of TDEs in these systems. The AT 2022wtn host galaxy properties suggest that it is in the early stages of the merger, therefore we may be witnessing the initial enhanced rate of TDEs in interacting galaxies before the post-starburst phase.
Ladattava julkaisu This is an electronic reprint of the original article. |  |
Julkaisussa olevat rahoitustiedot:
This work makes use of observations from the Las Cumbres Observatory global telescope network. The Liverpool Telescope is operated on the island of La Palma by Liverpool John Moores University in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias with financial support from the UK Science and Technology Facilities Council. These results made use of the Lowell Discovery Telescope (LDT) at Lowell Observatory. Lowell is a private, non-profit institution dedicated to astrophysical research and public appreciation of astronomy and operates the LDT in partnership with Boston University, the University of Maryland, the University of Toledo, Northern Arizona University, and Yale University. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile, as part of ePESSTO+ (the advanced Public ESO Spectroscopic Survey for Transient Objects Survey). ePESSTO + observations were obtained under ESO programs ID 111.24PR and 112.25JQ. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. We wish to recognize and acknowledge the cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. The SED machine is based upon work supported by the National Science Foundation under grant no. 1106171. ATLAS is primarily funded to search for near earth asteroids through NASA grants NN12AR55G, 80NSSC18K0284, and 80NSSC18K1575. Science products are made possible by grants Kepler/K2 J1944/80NSSC19K0112, HST GO-15889, and STFC grants ST/T000198/1 and ST/S006109/1 and contributions form University of Hawaii Institute for Astronomy, the Queen’s University Belfast, the Space Telescope Science Institute, the South African Astronomical Observatory, and The Millennium Institute of Astrophysics (MAS), Chile. Pan-STARRS telescopes are supported by the National Aeronautics and Space Administration under grants NNX12AR65G and NNX14AM74G, from the Near-Earth Object Observations Program. Data are processed at Queen’s University Belfast enabled through the STFC grants ST/P000312/1 and ST/T000198/1. This work was funded by ANID, Millennium Science Initiative, ICN12_009. The material is based upon work supported by NASA under award number 80GSFC21M0002. FO acknowledges support from MIUR, PRIN 2020 (grant 2020KB33TP) ‘Multimessenger astronomy in the Einstein Telescope Era (METE)’ and from INAF-MINIGRANT (2023): ‘SeaTiDE–Searching for Tidal Disruption Events with ZTF: the Tidal Disruption Event population in the era of wide field surveys’. MB, EC, and TP acknowledge the financial support from the Slovenian Research Agency (grants I0-0033, P1-0031, J1-8136, J1-2460, and Z1-1853) and the Young Researchers program. TWC acknowledges the Yushan Fellow Program by the Ministry of Education, Taiwan for the financial support (MOE-111-YSFMS-0008-001-P1). PC was supported by the Science & Technology Facilities Council [grants ST/S000550/1 and ST/W001225/1]. CPG acknowledges financial support from the Secretary of Universities and Research (Government of Catalonia) and by the Horizon 2020 Research and Innovation Programme of the European Union under the Marie Skłodowska-Curie and the Beatriu de Pinós 2021 BP 00168 programme, from the Spanish Ministerio de Ciencia e Innovación (MCIN) and the Agencia Estatal de Investigación (AEI) 10.13039/501100011033 under the PID2020-115253GA-I00 HOSTFLOWS project, and the program Unidad de Excelencia María de Maeztu CEX2020-001058-M. TEMB acknowledges financial support from the Spanish Ministerio de Ciencia e Innovación (MCIN), the Agencia Estatal de Investigación (AEI) 10.13039/501100011033, and the European Union Next Generation EU/PRTR funds under the 2021 Juan de la Cierva program FJC2021-047124-I and the PID2020-115253GA-I00 HOSTFLOWS project, from Centro Superior de Investigaciones Científicas (CSIC) under the PIE project 20215AT016, and the program Unidad de Excelencia María de Maeztu CEX2020-001058-M. TR acknowledges support from the Research Council of Finland project 350458 and the Cosmic Dawn Center (DAWN) which is funded by the Danish National Research Foundation under grant DNRF140. SM acknowledges support from the Research Council of Finland project 350458. RS acknowledges support from grants by the National Science Foundation (AST 2206730) and the David and Lucille Packard Foundation (PI: Kasliwal). MN is supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 948381) and by UK Space Agency grant no. ST/Y000692/1. IA acknowledges support from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement no. 852097), from the Israel Science Foundation (grant no. 2752/19), from the United States–Israel Binational Science Foundation (BSF; grant no. 2018166), and from the Pazy foundation (grant no. 216312). LM acknowledges support through a UK Research and Innovation Future Leaders Fellowship (grant no. MR/T044136/1). SGG acknowledges support from the ESO Scientific Visitor Programme.
