A hyper-runaway white dwarf in Gaia DR2 as a Type Iax supernova primary remnant candidate

Understand

Observations of stellar remnants linked to Type Ia and Type Iax supernovae are necessary to fully understand their progenitors.

• Multiple progenitor scenarios predict a population of kicked donor remnants and partially-burnt primary remnants, both moving with relatively high velocity.
• But only a handful of examples consistent with these two predicted populations have been observed.
• Here we report the likely first known example of an unbound white dwarf that is consistent with being the fully-cooled primary remnant to a Type Iax supernova.