The X-rays that fill the hohlraum bathe the fuel capsule
at its center, depositing energy on
the outside of the capule and heating the outer capsule layers (referred to as
the ablator).This hot
plasma rushes away from the capsule into the relative vacuum of the hohlraum.Conservation of momentum causes compression of the interior of the capsule (the rocket
effect), with an inward moving
shockwave converging on the fuel in
the capsule’s center.
A hydrodynamical simulation of the ablation and compression of a solid plastic sample by thermal X-rays. The X-rays are incident from the left.Hot,
tenuous material expands rapidly
off the (previously) solid surface
toward the left, while a shockwave
moving toward the right compresses
the remaining material.