  Direct measurement of axial magnetic field in the PF-1000 dense plasma focus
(DPF), and its reported correlation with neutron emission, call for a fresh
look at previous reports of existence of axial magnetic field component in the
DPF from other laboratories, and associated data suggesting toroidal
directionality of fast ions participating in fusion reactions, with a view to
understand the underlying physics. In this context, recent work dealing with
application of the hyperbolic conservation law formalism to the DPF is extended
in this paper to a curvilinear coordinate system, which reflects the shape of
the DPF current sheath. Locally-unidirectional shock propagation in this
coordinate system enables construction of a system of 7 one-dimensional
hyperbolic conservation law equations with geometric source terms, taking into
account all the components of magnetic field and flow velocity.
Rankine-Hugoniot jump conditions for this system lead to expressions for the
axial magnetic field and three components of fluid velocity having high ion
kinetic energy.

Plasma Physics