  Experimental asymmetries in fusion implosions can lead to magnetic field
generation in the hot plasma core. For typical parameters, previous studies
found that the magnetisation Hall parameter, given by the product of the
electron gyro-frequency and Coulomb collision time, can exceed one. This will
affect the hydrodynamics through inhibition and deflection of the electron heat
flux. The magnetic field source is the collisionless Biermann term, which
arises from the Debye shielding potential in electron pressure gradients. We
show that there is an additional source term due to the Z dependence of the
Coulomb collision operator. If there are ion composition gradients, such as
jets of carbon ablator mix entering the hot-spot, this source term can rapidly
exceed the Biermann fields. In addition, the Biermann fields are enhanced due
to the increased temperature gradients from carbon radiative cooling. With even
stronger self-generated fields, heat loss to the carbon regions will be
reduced, potentially reducing the negative effect of carbon mix.
