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 thick circumstellar material. It was the interaction of the blown up star and the product left over from this companion that gave rise to the strong radio signal, the obvious helium lines in the optical spectra and the infrared emission from SN 2020eyj.
An international group of astronomers has revealed the origin of an atomic supernova explosion. Strong emission lines of helium and the very first detection of such a supernova in radio waves reveal that the exploding white dwarf star had a helium-rich buddy.
Thermonuclear (Type Ia) supernovae are important for astronomers considering that they are utilized to determine the growth of deep space. Nevertheless, the origin of these explosions has actually remained an open concern. While it is developed that the explosion is that of a compact white dwarf star in some way accreting excessive matter from a buddy star, the exact procedure and the nature of the progenitor is not understood. The brand-new discovery of supernova SN 2020eyj established that the buddy star was a so-called helium star that had actually lost much of its material simply prior to the surge of the white dwarf.
” Once we saw the signatures of strong interaction with the material from the companion we tried to find it likewise in radio emission”, explains Erik Kool, post-doc at the Department of Astronomy at Stockholm University and lead author of the paper. “The detection in radio is in fact the first one of a Type Ia supernova– something astronomers have attempted to do for decades.”
Artist impression of the double star system with a compact white dwarf star accreting matter from a helium-rich donor companion, surrounded by dirty and dense circumstellar material. It was the interaction of the exploded star and the product left over from this buddy that gave rise to the strong radio signal and the obvious helium lines in the optical spectra of SN 2020eyj. Credit: Adam Makarenko/W. M. Keck Observatory
SN 2020eyj was discovered by the Zwicky Transient Facility electronic camera on Palomar Mountain and was followed with a number of centers consisting of the Nordic Optical Telescope (NOT) on La Palma, the large Keck telescope on Hawaii and the electronic Multi-Element Radio Linked Interferometer Network (e-MERLIN) which is a range of 7 radio telescopes in Great Britain.
Supernova 2020eyj was likewise incredibly intense at infrared wavelengths measuring up to a few of the brightest supernovae observed at these wavelengths. This brightness was interpreted as thermal emission from interstellar dust particles mixed in the product surrounding the supernova.
” The radio, optical, and infrared observations are all consistent with the buddy star losing a significant amount of mass prior to the surge of the white dwarf. This exciting discovery provides better understanding of explosions of white dwarfs as supernovae utilized for cosmological measurements” according to Prof. Seppo Mattila, Department of Physics and Astronomy at University of Turku who was a co-author of the paper with his main contribution in the analysis of the infrared and radio observations.
For more on this research:
Referral: “A radio-detected type Ia supernova with helium-rich circumstellar product” 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 product is published in Nature and is led by Erik Kool from the Department of Astronomy at Stockholm University and describes the first radio detection of a Type Ia supernova. The work involved scientists from institutes across the world, consisting of University of Turku, Caltech, Weizmann Institute, IAA-CSIC, NAOJ, Macquarie University, and Trinity College Dublin.
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 thick circumstellar material. While it is established that the explosion is that of a compact white dwarf star in some way accreting too much matter from a companion star, the exact procedure and the nature of the progenitor is not known. The brand-new discovery of supernova SN 2020eyj established that the buddy star was a so-called helium star that had lost much of its material simply prior to the surge of the white dwarf.
Artist impression of the double star system with a compact white dwarf star accreting matter from a helium-rich donor companion, surrounded by thick and dusty circumstellar material.