Ignition Scaling Laws and Their Application to Capsule Design

In this paper a two pronged approach is taken to investigating the energy required for ignition of inertial confinement fusion capsules. A series of one dimensional LASNEX simulations is performed to create a database of barely ignited capsules that span the parameter regime Of interest. This database is used to develop scaling laws for the ignition energy in terms of both the stagnated capsule parameters and the inflight capsule parameters, and explore the connection between these two parameter sets. The second part of this paper examines how much extra energy is required to overcome the effect of the inevitable surface imperfections that are amplified during the implosion process and can lead to capsule break up in flight or to mix of cold fuel into the hotspot, both of which can cause the capsule to fail to ignite. By means of an example, the optimization of a capsule with fixed adiibat, drive pressure, and absorbed energy is performed; the capsule that is maximally robust to these failure modes is found