Magnetic Structure and Gas Dynamics Measurements of the Bryn Mawr Magnetohydrodynamic Experiment Coaxial Plasma Source

Measurements of the magnetic structure and gas dynamics of the coaxial plasma source on the Bryn Mawr Magnetohydrodynamic Experiment (BMX) are reported. The gun consists of three pulsed magnetic coils, two outer and one inner. The coils are oriented such to generate a radial magnetic field at the mouth of the gun in order to provide a stiff, but brittle stuffing field for the ejected plasma which is necessary for sustained injection of plasma helicity. Four Parker puff valves inject pure hydrogen gas into the chamber. A fast ionization gauge is used to measure gas flow and distribution using time of flight.