What happens after a merger of massive double white dwarfs?

Double white dwarf (WD) binaries are vital gravitational wave sources in our galaxy, and their mass is expounded to the sort Ia supernovae, electron seize supernovae and millisecond pulsars.

Double WDs in binary programs can merge collectively because of the gravitational wave radiation. Nevertheless, the evolution of postmerger remnants from such a merger stays unclear.

Now, a analysis group led by assistant professor Wu Chengyuan from the Yunnan Observatories of the Chinese language Academy of Sciences investigated the the evolutionary outcomes from the merger of oxygen-neon WD and carbon-oxygen WD.

The research was revealed within the Astrophysical Journal Letters on Feb. 22.

The researchers constructed corresponding fashions to research the evolution of merger remnants. They discovered that such merger remnants can evolve to carbon-oxygen giants, and their evolutionary outcomes are associated to their total lots.

Underneath the fastened wind mass-loss prescription, remnants with lots lighter than 1.90M⊙ might evolve to oxygen-neon WDs, whereas the remnants with lots larger than 1.95M⊙ might expertise electron seize supernova explosions to develop into oxygen-neon-iron WDs.

“Our outcome implies that the super-Chandrasekhar mass remnants originated from the mergers of oxygen-neon WD and carbon-oxygen WD can’t type neutron stars, which challenged the normal understandings,” stated Wu.

Furthermore, they used the corresponding fashions to elucidate the oxygen-rich object IRAS 00500+6713 (J005311) situated within the infrared nebula in Cassiopeia. The spectrum of this object is much like that of the oxygen-rich Wolf-Rayet stars, and it has comparatively excessive wind mass-loss charge and very excessive wind velocity.

At current, the origin of this object continues to be unclear. Wu defined the observational options of this object through the use of their fashions, and located that this object was originated from the merger of a 1.08M⊙ oxygen-neon WD with a 0.52M⊙ carbon-oxygen WD.