Three-dimensional simulations of gravitationally confined detonations compared to observations of SN 1991T

Understand

The gravitationally confined detonation (GCD) model has been proposed as a possible explosion mechanism for Type Ia supernovae in the single-degenerate evolution channel.

• Driven by buoyancy, a deflagration flame rises in a narrow cone towards the surface.
• For the most part, the flow of the expanding ashes remains radial, but upon reaching the outer, low-pressure layers of the white dwarf, an additional lateral component develops.
• This makes the deflagration ashes converge again at the opposite side, where the compression heats fuel and a detonation may be launched.