A helium-burning white dwarf binary as a supersoft X-ray source

J. Greiner (), C. Maitra, F. Haberl, R. Willer, J. M. Burgess, N. Langer, J. Bodensteiner, D. A. H. Buckley, I. M. Monageng, A. Udalski, H. Ritter, K. Werner, P. Maggi, R. Jayaraman and R. Vanderspek
Additional contact information
J. Greiner: Max-Planck-Institut für extraterrestrische Physik
C. Maitra: Max-Planck-Institut für extraterrestrische Physik
F. Haberl: Max-Planck-Institut für extraterrestrische Physik
R. Willer: Max-Planck-Institut für extraterrestrische Physik
J. M. Burgess: Max-Planck-Institut für extraterrestrische Physik
N. Langer: Universität Bonn
J. Bodensteiner: ESO – European Organisation for Astronomical Research in the Southern Hemisphere
D. A. H. Buckley: South African Astronomical Observatory
I. M. Monageng: South African Astronomical Observatory
A. Udalski: University of Warsaw
H. Ritter: Max-Planck-Institut für Astrophysik
K. Werner: Universität Tübingen
P. Maggi: Université de Strasbourg, CNRS, Observatoire astronomique de Strasbourg, UMR 7550
R. Jayaraman: Massachusetts Institute of Technology
R. Vanderspek: Massachusetts Institute of Technology

Nature, 2023, vol. 615, issue 7953, 605-609

Abstract: Abstract Type Ia supernovae are cosmic distance indicators1,2, and the main source of iron in the Universe3,4, but their formation paths are still debated. Several dozen supersoft X-ray sources, in which a white dwarf accretes hydrogen-rich matter from a non-degenerate donor star, have been observed5 and suggested as Type Ia supernovae progenitors6–9. However, observational evidence for hydrogen, which is expected to be stripped off the donor star during the supernova explosion10, is lacking. Helium-accreting white dwarfs, which would circumvent this problem, have been predicted for more than 30 years (refs. 7,11,12), including their appearance as supersoft X-ray sources, but have so far escaped detection. Here we report a supersoft X-ray source with an accretion disk whose optical spectrum is completely dominated by helium, suggesting that the donor star is hydrogen-free. We interpret the luminous and supersoft X-rays as resulting from helium burning near the surface of the accreting white dwarf. The properties of our system provide evidence for extended pathways towards Chandrasekhar-mass explosions based on helium accretion, in particular for stable burning in white dwarfs at lower accretion rates than expected so far. This may allow us to recover the population of the sub-energetic so-called Type Iax supernovae, up to 30% of all Type Ia supernovae13, within this scenario.

Date: 2023
References: Add references at CitEc
Citations:

Downloads: (external link)
https://www.nature.com/articles/s41586-023-05714-4 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:615:y:2023:i:7953:d:10.1038_s41586-023-05714-4

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/s41586-023-05714-4

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().