Pulsating delayed detonation

This type of model was introduced to find a mechanism being able to supplement a too weak deflagration. As we saw earlier, it is rather difficult to explode a supernova by means of a deflagration. In this model, the first deflagration does not allow the explosion. When the densities become too low, the flame is choked to leave room to a gravitational collapse of dwarf white. It is this gravitational collapse which would allow the lighting of a detonation (after one or more recontractions or pulsations) involving the destruction of star.

This type of explosion produces only little ${ }^{56}$Ni but it allows the synthesis of substantial quantities of silicon and calcium. It could thus be at the origin of the under-luminous supernovæ of the type of 1991bg. Globalement, this type of model has the same advantages as the models of delayed detonation. Once again, the parameters must be adjusted finely to allow an explosion reproducing the observations. Lastly, this type of model is now probably cancelled by the most recent models of deflagration 3d which seem to be able to produce an explosion under all the conditions.