Artists impression of helium-rich product from a buddy star accreting onto a white dwarf. Before the explosion, a large amount of material is removed from the companion. The research team wishes to clarify the relationship between the given off strong radio waves and this removed material. Credit: Adam Makarenko/W. M. Keck Observatory
In the most current concern of the journal Nature, astronomers from Stockholm University reveal the origin of an atomic supernova surge. Strong emission lines of helium and the very first detection of such a supernova in radio waves show that the taking off white dwarf star had a helium-rich companion.
Researchers from Stockholm University have found a thermonuclear supernovas origin traced to a helium-rich buddy star of a white dwarf. This first-ever detection of a supernova in radio waves clarifies the nature and procedures leading to Type Ia supernovae, important for measuring deep spaces growth. The finding assists fix the enduring concern about the process resulting in the explosion of a white dwarf star and the nature of its progenitor, determined here as a helium star that had lost much of its product just prior to the white dwarfs surge.
While it is established that the explosion is that of a compact white dwarf star somehow accreting too much matter from a companion star, the precise process and the nature of the progenitor are not known. The new discovery of supernova SN 2020eyj established that the companion star was a helium star that had lost much of its material simply prior to the explosion of the white dwarf.
Artist impression of the double star system with a compact white dwarf star accreting matter from a helium-rich donor buddy, surrounded by thick and dusty circumstellar material. It was the interaction of the exploded star and the material left over from this buddy that offered increase to the strong radio signal and the conspicuous helium lines in the optical spectra of SN 2020eyj.
Artist impression of the double star system with a compact white dwarf star accreting matter from a helium-rich donor companion, surrounded by dusty and dense circumstellar product. It was the interaction of the blown up star and the product left over from this buddy that triggered the strong radio signal and the noticeable helium lines in the optical spectra of SN 2020eyj. Credit: Adam Makarenko/W. M. Keck Observatory
” Once we saw the signatures of strong interaction with the product from the companion we attempted to likewise spot it in radio emission,” describes Erik Kool, post-doc at the Department of Astronomy at Stockholm University and lead author of the paper. “The detection in radio is the very first among a Type Ia supernova– something astronomers have tried to do for years.”
Supernova 2020eyj was discovered by the Zwicky Transient Facility video camera on Palomar mountain, where the Oskar Klein Centre at Stockholm University are members.
” The Nordic Optical telescope on La Palma was fundamental for following up this supernova,” states Professor Jesper Sollerman at the Department of Astronomy and co-author of the paper.” As were spectra from the large Keck telescope on Hawaii that instantly exposed the really unusual helium-dominated product around the exploded star.”
Erik Kool (center) and Joel Johansson (left) are post-docs at the Oskar Klein Centre at Stockholm University and lead authors of this paper together with professor Jesper Sollerman (best) from the Department of Astronomy. Credit: Magnus Näslund
” This is plainly an extremely unusual Type Ia supernova, but still related to the ones we use to determine the expansion of deep space,” adds Joel Johansson from the Department of Physics.
” While normal Type Ia supernovae appear to constantly take off with the very same brightness, this supernova tells us that there are various paths to a white dwarf star surge,” he includes.
Reference: “A radio-detected type Ia supernova with helium-rich circumstellar material” by Erik C. Kool, Joel Johansson, Jesper Sollerman, Javier Moldón, Takashi J. Moriya, Seppo Mattila, Steve Schulze, Laura Chomiuk, Miguel Pérez-Torres, Chelsea Harris, Peter Lundqvist, Matthew Graham, Sheng Yang, Daniel A. Perley, Nora Linn Strotjohann, Christoffer Fremling, Avishay Gal-Yam, Jeremy Lezmy, Kate Maguire, Conor Omand, Mathew Smith, Igor Andreoni, Eric C. Bellm, Joshua S. Bloom, Kishalay De, Steven L. Groom, Mansi M. Kasliwal, Frank J. Masci, Michael S. Medford, Sungmin Park, Josiah Purdum, Thomas M. Reynolds, Reed Riddle, Estelle Robert, Stuart D. Ryder, Yashvi Sharma and Daniel Stern, 17 May 2023, Nature.DOI: 10.1038/ s41586-023-05916-w.
The paper “A radio-detected Type Ia supernova with helium-rich circumstellar material” is released in Nature and is led by Erik Kool from the Department of Astronomy at Stockholm University and explains the first radio detection of a Type Ia supernova. Co-authors from Stockholm University are Joel Johansson, Jesper Sollerman, Steve Schulze, Peter Lundqvist, Sheng Yang, and Conor Omand. This work involved scientists from institutes across the world, including Caltech, Weizmann Institute, IAA-CSIC, NAOJ, Macquarie University, and Trinity College Dublin.
Funding: Vetenskapsrådet (Swedish Research Council), Wenner-Gren Foundation.
Artists impression of helium-rich product from a buddy star accreting onto a white dwarf. The finding assists solve the enduring concern about the procedure leading to the surge of a white dwarf star and the nature of its progenitor, determined here as a helium star that had actually lost much of its product just prior to the white dwarfs explosion.
The brand-new discovery of supernova SN 2020eyj established that the companion star was a helium star that had lost much of its product just prior to the surge of the white dwarf.