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Updated: Jul 18, 2026

A 100 KW Class Applied-field Magnetoplasmadynamic Thruster
Published on: December 22, 2018
Efficient generation of closed magnetic flux surfaces in a large spherical tokamak using coaxial helicity injection
R Raman1, B A Nelson, M G Bell
1University of Washington, Seattle, Washington, USA.
Abstract:
A method of coaxial helicity injection has successfully produced a closed flux current without the use of the central solenoid in the NSTX device, on a size scale closer to a spherical torus reactor, for a proof-of-principle demonstration of this concept. For the first time, a remarkable 60 times current multiplication factor was achieved. Grad-Shafranov plasma equilibrium reconstructions are used to verify the existence of closed flux current. In some discharges the generated current persists for a surprisingly long time approximately 400 ms.
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