Spin-Up/Spin-Down models for Type Ia Supernovae

Understand

In the single degenerate scenario for Type Ia supernova (SNeIa), a white dwarf (WD) must gain a significant amount of matter from a companion star.

• Because the accreted mass carries angular momentum, the WD is likely to achieve fast spin periods, which can increase the critical mass, $M_{crit}$, needed for explosion.
• When $M_{crit}$ is higher than the maximum mass achieved by the WD, the WD must spin down before it can explode.
• This introduces a delay between the time at which the WD has completed its epoch of mass gain and the time of the explosion.