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Experimental study of the recombination of a drifting low temperature plasma in the divertor simulator Mistral-B

Cedric Brault·Alexandre Escarguel·Mohamed Koubiti·Roland Stamm·Thiery Pierre·Kamal Quotb·Didier Guyomarc'H
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Abstract

In a new divertor simulator, an ultra-cold (Te<1 eV) high density recombining magnetized laboratory plasma is studied using probes, spectroscopic measurements, and ultra-fast imaging of spontaneous emission. The Mistral-B device consists in a linear high density magnetized plasma column. The ionizing electrons originate from a large cathode array located in the fringing field of the solenoid. The ionizing electrons are focused in a 3 cm diameter hole at the entrance of the solenoid. The typical plasma density on the axis is close to 2.10^18 m-3. The collector is segmented into two plates and a transverse electric field is applied through a potential difference between the plates. The Lorentz force induces the ejection of a very-low temperature plasma jet in the limiter shadow. The characteristic convection time and decay lengths have been obtained with an ultra-fast camera. The study of the atomic physics of the recombining plasma allows to understand the measured decay time and to explain the emission spectra.

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Cedric Brault, Alexandre Escarguel, Mohamed Koubiti, Roland Stamm, Thiery Pierre, Kamal Quotb, Didier Guyomarc'H. 2004-10-22. Experimental study of the recombination of a drifting low temperature plasma in the divertor simulator Mistral-B. https://arxiv.org/abs/physics/0410219

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