A1 Refereed original research article in a scientific journal
AT 2024wpp: an extremely luminous fast ultraviolet transient powered by accretion onto a black hole; 
Authors: Perley, Daniel A.; Ho, Anna Y. Q.; McGrath, Zoe; Camilo, Michael; Sevilla, Cassie; Chen, Ping; Schroeder, Genevieve; Govreen-Segal, Taya; Bochenek, Aleksandra; Qin, Yu-Jing; Gillanders, James H.; Amend, Benjamin; Anderson, Joseph P.; Andreoni, Igor; Aryan, Amar; Bellm, Eric C.; Bloom, Joshua S.; de Boer, Thomas; Carney, Jonathan; Caiazzo, Ilaria; Chambers, Ken C.; Charalampopoulos, Panos; Chen, Ting-Wan; Chen, Tracy X.; Coughlin, Eric R.; Coughlin, Michael; Dennefeld, Michel; Dimitriadis, Georgios; Fremling, Christoffer; Frostig, Danielle; Gal-Yam, Avishay; Galbany, Lluis; Gangopadhyay, Anjashay; Ghendrih, Melzie; Graham, Matthew J.; Gromadzki, Mariusz; Groom, Steven L.; Gutierrez, Claudia P.; Hinds, K. -Ryan; Huber, Mark E.; Inserra, Cosimo; Kaiser, Benjamin C.; Kasliwal, Mansi M.; Koivisto, Niilo E.; Lin, Chien-Cheng; Liu, Chang; Lowe, Thomas B.; Magnier, Eugene; Mahabal, Ashish A.; Milligan, Andrew; Minguez, Paloma; Mo, Geoffrey; Muller-Bravo, Tomas E.; Nicholl, Matt; Pessi, Priscila J.; Pignata, Giuliano; Purdum, Josiah; Rehemtulla, Nabeel; Rich, R. Michael; Sahu, Anwesha; Singh, Avinash; Smartt, Stephen J.; Smith, Ian A.; Sollerman, Jesper; Srinivasaragavan, Gokul; Srivastav, Shubham; Stein, Robert D.; Schulze, Steve; Tweddle, Jack W.; Wainscoat, Richard; Wise, Jacob L.; Yan, Lin; Young, David R.
Publisher: Oxford University Press
Publication year: 2026
Journal: Monthly Notices of the Royal Astronomical Society
Article number: stag678
Volume: 549
Issue: 1
ISSN: 0035-8711
eISSN: 1365-2966
DOI: https://doi.org/10.1093/mnras/stag678
Publication's open availability at the time of reporting: Open Access
Publication channel's open availability : Open Access publication channel
Web address : https://academic.oup.com/mnras/article/549/1/stag678/8651295
Self-archived copy’s web address: https://research.utu.fi/converis/portal/detail/Publication/526483878
Self-archived copy's licence: CC BY
Self-archived copy's version: Publisher`s PDF
We present the discovery of AT 2024wpp (‘Whippet’), a fast and luminous 18cow-like transient. At a redshift of z = 0.0868, revealed by Keck Cosmic Web Imager spectroscopy of its faint star-forming host, it is the fourth-nearest example of its class to date. Rapid identification of the source in the Zwicky Transient Facility data stream permitted ultraviolet-through-optical observations to be obtained prior to peak, allowing the first determination of the peak bolometric luminosity (2 × 1045 erg s−1 ), maximum photospheric radius (1015 cm), and total radiated energy (1051 erg) of an 18cow-like object. We present results from a comprehensive multiwavelength observing campaign, including a far-ultraviolet spectrum from the Cosmic Origins Spectrograph on the Hubble Space Telescope and deep imaging extending > 100 d post-explosion from the Very Large Telescope, Hubble Space Telescope, Very Large Array, and Atacama Large Millimetre Array. We interpret the observations under a model in which a rapidly accreting central engine blows a fast (∼ 0.2 c) wind into the surrounding medium and irradiates it with X-rays. The high Doppler velocities and intense ionization within this wind prevent identifiable spectroscopic features from appearing in the ejecta or in the surrounding circumstellar material. Weak H and He signatures do emerge in the spectra after 35 d in the form of double-peaked narrow lines. Each peak is individually narrow (full width δv ∼ 3000 km s−1 ) but the two components are separated by v ∼ 6600 km s−1 , indicating stable structures of denser material, possibly representing streams of tidal ejecta or an ablated companion star.
Keywords:
radio continuum: transients, stars: black holes, supernovae: individual: AT2024wpp
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https://academic.oup.com/mnras/article/549/1/stag678/8651295#562788268
