Study of correlation of deuterium content in a-C:D dust induced by laser irradiation from the co-deposited surface with the grain size and velocity
2014 (English)In: Physica Scripta, ISSN 0031-8949, E-ISSN 1402-4896, Vol. T161, 014010- p.Article in journal (Refereed) Published
In the study described here, the laser ablation method was applied to clean thick (40-60 m) a-C: D co-deposits on the ALT-II limiter blade from the TEXTOR tokamak, and at the same time to characterize the ejected particles formed during ablation and measure the amount of fuel carried by them. Ablation was accomplished by similar to 3.5 ns, 0.5 J Nd: YAG laser pulses in either vacuum or an O-2 atmosphere at different pressures. Fast camera tracking of the process provided an estimate of the population and velocity of up to 100ms(-1) for larger dust particles. In the same experiment, the dust particles were caught using ultra-light Si aerogel collectors placed in front of the ablation target. SEM analysis of aerogel surfaces verified the speed estimate, providing the trapped particles' size distribution and particle yield during ablation. The D/C atomic concentration ratio was measured with the 3HE ion beam nuclear reaction analysis method in deposited layers before ablation and with a micro-ion beam in individual particles on aerogel collectors. This indicated that most of the D was thermally released during ablation, leaving no more than 5% of its original amount in the particles. The effect of ablation conditions on the acceleration of ejected particles, their population, composition and D content is the main subject of this paper.
Place, publisher, year, edition, pages
Institute of Physics (IOP), 2014. Vol. T161, 014010- p.
laser ablation, dusty plasmas, plasma dynamics, fuel retention and removal, materials for fusion reactors
IdentifiersURN: urn:nbn:se:kth:diva-149515DOI: 10.1088/0031-8949/2014/T161/014010ISI: 000339620200011ScopusID: 2-s2.0-84901498999OAI: oai:DiVA.org:kth-149515DiVA: diva2:739860
International Conference on Research and Applications of Plasmas, PLASMA 2013; Warsaw; Poland; 2 September 2013 through 6 September 2013
QC 201408222014-08-222014-08-222015-06-23Bibliographically approved