Hydrodynamic instability of ablation fronts in inertial confinement fusion

An analytical model for the Rayleigh–Taylor instability of an ablation front is developed by decoupling the instability analysis from the corona physics. Thus, the validity of the resulting dispersion relation is not limited by a particular approximation for the unperturbed profiles. In consequence, it turns out to be suitable for calculating the instability growth rate by using the corona profiles obtained from one-dimensional simulations. The model applies to the regime with large and intermediate Froude numbers, for which Fr⩾10−2. However, it is well behaved also for Fr⩽10−2, allowing for its application to situations with arbitrary Froude numbers. Besides, the model shows the relevance of the stabilizing effects of the lateral transport of mass and momentum.