Type Iax supernova
A type Iax supernova is a rare subtype of type Ia supernova, which leaves behind a remnant star, known as zombie star, rather than completely dispersing the white dwarf.[1][2][3][4][5] Type Iax supernovae are similar to type Ia, but have a lower ejection velocity and lower luminosity.[6] Type Iax supernovae may occur at a rate between 5 and 30 percent of the Ia supernova rate. Thirty supernovae have been identified in this category.[7]
In a binary system consisting of a white dwarf and a companion star, the white dwarf strips away material from its companion. Normally the white dwarf would eventually reach a critical mass, and fusion reactions would make it explode and completely dissipate it, but in a Type Iax supernova, only a part of the dwarf's mass is lost.[8]
Candidate observed instances
Supernova
The proposed formation scenario for SN 2012Z is that the original system at the heart of the supernova was a binary pair of large, but otherwise ordinary
There were images of the area from before the supernova, allowing before and after images, and the process of the supernova to be studied. To test the zombie star hypothesis, the area was observed again a few years after the event. The authors found that the decline of the light curve was consistent with the existence of a radioactively-heated bound remnant, but that it was difficult to come up with a model that could explain the whole light curve.[9]
This discovery is a milestone in a decades long search by astronomers for such an occurrence; the observation of SN 2012Z was the first time astrophysicists were able to identify a star system that later went supernova.[8]
SN 2008ha may be a type Iax supernova, but significantly weaker than SN 2012Z.[3]
SN 1181
SN 1181 was observed by Chinese and Japanese astronomers in 1181 AD. The amateur astronomer Dana Patchick first discovered the nebula Pa 30 with WISE. The nebula Pa 30 was connected to SN 1181 by astronomers and has the central star IRAS 00500+6713. The central star is an oxygen-rich Wolf–Rayet star and is the result of a merger of a CO (carbon-oxygen) white dwarf and an ONe (oxygen–neon–magnesium) white dwarf in a type Iax supernova. This makes IRAS 00500+6713 a confirmed zombie star. Pa 30 and IRAS 00500+6713 is the only known remnant of a type Iax in the Milky Way.[10][11]
References
- ^ Hubbard, Amy (6 August 2014). "Hubble sees 'zombie star' lurking in space: What it is, why it matters". Los Angeles Times. Retrieved 30 October 2014.
- ^ "Hubble discovers 'zombie star' haunting the universe". CNET. Retrieved 30 October 2014.
- ^ a b c Weaver, Donna; Villard, Ray (6 August 2014). "NASA's Hubble Finds Supernova Star System Linked to Potential "Zombie Star"". HubbleSite – NewsCenter. NASA. Retrieved 30 October 2014.
- Slate Magazine(Video). 12 August 2014. Retrieved 30 October 2014.
- Time Magazine. Retrieved 30 October 2014.
- S2CID 4464556.
- Washington Post. Retrieved 30 October 2014.
- ^ a b Choi, Charles Quixote (6 August 2014). "Supernovas Might Create Weird 'Zombie Stars'". Space.com. Retrieved 30 October 2014.
- .
- Bibcode:2023arXiv231103700R.
- ISSN 2041-8205.