  This paper focuses on the process of magnetic flux generation in ICF
implosions. Hot-spots are shown to be dominated by fields generated during
stagnation, when the temperature and density gradients are largest. A scaling
of hot-spot magnetic flux is derived and compared with simulations, revealing
that perturbations with both larger amplitudes and higher mode numbers generate
more magnetic flux. The model allows for greater understanding of which target
designs will be susceptible to MHD effects. For example, the model can be used
to ascertain the time when most magnetic flux is generated. If generation is
weighted more towards early times, then more high-mode magnetic field loops
will be present. A hot-spot with no high-mode perturbations at time of peak
neutron production can still contain significant magnetic flux on those scales.
By assuming that magnetic flux is deposited at the hot-spot edge by Nernst
advection, the model can be used to post-process radiation-hydrodynamics data
to estimate magnetic field strengths and magnetizations.
