Wake potential of a test charge using the stationary phase method
2005 (English)Conference paper (Refereed)
The linear response of a dusty (complex) plasma to a moving test charge can be determined using an appropriate plasma dielectric function and a three dimensional Fourier analysis. Many analytical results have been found for a slowly moving test charge. For intermediate and large velocities numerical methods of integration are commonly used. However general asymptotic results valid at large distances can be found, using a combination of the residue calculus applied to the zeroes of the dielectric function and the method of stationary phase for integration over a wave vector component. The method can be expressed in terms of conditions on the group and phase velocity of waves in the reference frame of the moving test charge. In particular for a given radial direction the asymptotic response is determined by wave vectors for which the group velocity is directed radially outwards. The analysis is close to that due to Kelvin for ship waves in deep water. An essential difference is that in the present case three spatial dimensions are involved instead of only two, and also that the dispersion relation for plasma waves is more complicated.
Place, publisher, year, edition, pages
2005. 2310-2313 p.
, Europhysics Conference Abstracts, Volume 3
Fusion, Plasma and Space Physics
IdentifiersURN: urn:nbn:se:kth:diva-148503ScopusID: 2-s2.0-84873401883ISBN: 978-162276332-0OAI: oai:DiVA.org:kth-148503DiVA: diva2:749440
32nd European Physical Society Conference on Plasma Physics and Controlled Fusion combined with the 8th International Workshop on Fast Ignition of Fusion Targets; Tarragona; Spain; 27 June 2005 through 1 July 2005
QC 201409242014-09-242014-08-082014-09-24Bibliographically approved