THOMAS MECHANISM IN ELECTRON CAPTURE TO THE CONTINUUM

     V. D. Rodr\'{\i}guez$^\sharp$ and R. O. Barrachina$^\ast$

$^\sharp$Departamento de F\'{\i}sica, Universidad de Buenos Aires, FCEyN,
1428
Buenos Aires, Argentina
$^\ast$Centro At\'omico Bariloche and Instituto Balseiro, 8400 S. C. de
Bariloche, R\'{\i}o Negro, Argentina

Thomas mechanism is  theoretically shown to be present for electron capture
to the continuum (ECC) in ion atom ionizing collisions.  By focusing on the
recoil ion momentum distributions, a prominent peak structure at 60$^\circ$
from the backward direction is observed  near  the  kinematical  threshold.
This recoil ion critical angle corresponds to  the Thomas double scattering
mechanism for electron capture.