Type Iax supernova
Dwarf star remnant of a supernova / From Wikipedia, the free encyclopedia
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]