Compact toroid formation experiments

Abstract

Summary form only given, as follows. A compact toroid (CT) formation experiment is discussed. The device has coaxial electrode diameters of 0.9 m (inner) and 1.25 m (outer) and an electrode length of ~1.2 m, including an expansion drift section. The CT is formed by a 0.1-0.2-T initial radial magnetic field embedded coaxial puff gas discharge. The gas puff is injected with an array of 60 pulsed solenoid driven fast valves. The formation discharge is driven by a 108-μF, 40-100-kV, 86-540-kJ, 2-5-MA capacitor discharge with ~20-nH initial total discharge inductance. The hardware includes transmission line connections for a Shiva Star (1300-μF, up to 120-kV, 0.4-MJ) capacitor bank driven acceleration discharge. Experimental measurements include current and voltage; azimuthal, radial, and axial magnetic field at numerous locations; fast photography and optical spectroscopy; and microwave, CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> laser, and He-Ne laser interferometry. Auxiliary experiments include Penning ionization gauge, pressure probe, and breakdown gas trigger diagnostics of gas injection, and Hall probe measurements of magnetic field injection