Theta pinch experiments at nT-Tao

nT-Tao is developing the compact-core fusion concept. This concept aims to reach fusion conditions in D-T plasma of T~10keV, n~10²²m^-3 with confinement time of τ_E~10’s of milliseconds. To approach this plasma regime a linear theta-pinch device was built. The device comprises a ~0.7 m length tube with bore diameter of 65 mm and a single turn coil. The coil is fed by a ~85 kJ, 60 kV capacitor bank discharged using rail-gap switches coupled to a low inductance bi-plate transmission line. A current pulse of ~1 MA with sub microsecond rise time forms the hot and dense pinch plasma.

This small yet powerful device can fire many shots per day; thus, provides a convenient platform for test and development of power generators, coils and diagnostics. We will present results of the recent characterization of the pinch plasma using X-ray spectroscopy, visible spectroscopy, Thomson scattering and magnetic coils.

The system was also used to test an innovative concept of quench-resistant superconducting coil. Experiments with the presence of the superconductor bias field will also be presented.