A retractable electron emitter for the creation of unperturbed pure electron plasmas
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States)
A retractable electron emitter has been constructed for the creation of unperturbed pure electron plasmas on magnetic surfaces in the Columbia Non-neutral Torus stellarator. The previous method of electron emission using emitters mounted on stationary rods limited the confinement time to 20 ms. A pneumatically driven system that can retract from the magnetic axis to the last closed flux surface in less than 20 ms while filling the surfaces with electrons was designed. The motion of the retractable emitter was modeled with a system of dynamical equations. The measured position versus time of the emitter agrees well with the model and the fastest axis-to-edge retraction was measured to be 20 ms with 40 psig helium gas driving the pneumatic piston.
- OSTI ID:
- 20953239
- Journal Information:
- Review of Scientific Instruments, Vol. 78, Issue 1; Other Information: DOI: 10.1063/1.2431090; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
- Country of Publication:
- United States
- Language:
- English
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