  Dark matter that is capable of sufficiently heating a local region in a white
dwarf will trigger runaway fusion and ignite a type Ia supernova. This was
originally proposed in Graham et al. (2015) and used to constrain primordial
black holes which transit and heat a white dwarf via dynamical friction. In
this paper, we consider dark matter (DM) candidates that heat through the
production of high-energy standard model (SM) particles, and show that such
particles will efficiently thermalize the white dwarf medium and ignite
supernovae. Based on the existence of long-lived white dwarfs and the observed
supernovae rate, we derive new constraints on ultra-heavy DM which produce SM
particles through DM-DM annihilations, DM decays, and DM-SM scattering
interactions in the stellar medium. As a concrete example, we rule out
supersymmetric Q-ball DM in parameter space complementary to terrestrial
bounds. We put further constraints on DM that is captured by white dwarfs,
considering the formation and self-gravitational collapse of a DM core which
heats the star via decays and annihilations within the core. It is also
intriguing that the DM-induced ignition discussed in this work provide an
alternative mechanism of triggering supernovae from sub-Chandrasekhar,
non-binary progenitors.
