2012/04/10 by N. R. Badnell, C. P. Ballance, Badnell, N. R. +5
Physics and Astronomy · #Atomic Physics (physics.atom-ph) #FOS: Physical sciences #physics.atom-ph
paper · pdf · doi:10.48550/arxiv.1204.2187
10 pages, 8 figures, submitted to Phys.Rev.A
arxiv created 2012/04/10 · arxiv updated 2012/04/11
A recent measurement of the dielectronic recombination (DR) of W20+ [Schippers et al Phys. Rev. A83, 012711 (2011)] found an exceptionally large contribution from near threshold resonances (<1eV). This still affected the Maxwellian rate coefficient at much higher temperatures. The experimental result was found to be a factor 4 or more than that currently in use in the 100-300eV range which is of relevance for modeling magnetic fusion plasmas. We have carried-out DR calculations with AUTOSTRUCTURE which include all significant single electron promotions. Our intermediate coupling (IC) results are more than a factor of 4 larger than our LS-coupling ones at 1eV but still lie a factor 3 below experiment here. If we assume complete (chaotic) mixing of near-threshold autoionizing states then our results come into agreement (to within 20%) with experiment below about 2eV. Our total IC Maxwellian rate coefficients are 50-30% smaller than those based-on experiment over 100-300eV.