Bremsstralung analysis through the microwave cutoff and afterglow performances

Lamoureux M.1, Mironov V.2, Niimura M.3, Kidera M.3, Nakagawa K.3
1Laboratoire de Dynamique des Ions, Atomes et Molecules, Univ. Pierre et Marie Curie, Paris, France
2Joint Institute for Nuclear Research (JINR), Dubna, Russia
3The Institute of Physical and Chemical Research (RIKEN), Japan

Bremsstralung spectra with a very good energy resolution have been obtained for various time slabs of a few ms throughout the microwave cutoff. In a recent work (1) we had noticed+ and explained why the enhancement of the extracted high charge currents by the afterglow effect is more pronounced when the X-ray emission in the heating stage is more intense.

In the present communication, we give some additional information deduced from our spectra. We indicate estimates of the temperature parameter and of the density of the hot electron population at various times. For this purpose the method presented in ref.(3) was adapted to argon. We also determine the maximum energy reached by the electrons in the steady state; the spare results seem to follow the scaling law indicated in Geller's book (4).

+coherently with a passing remark in ref. (2).

(1) M. Kidera, M. Lamoureux, V. Mironov, T. Nakagawa and G. Shirkov, recently submitted to Rev. Sci. Instrum.
(2) C.E. Hill and K. Langbein, Proceedings of the 7th International Conference on Ion Sources, Taormina, Italy, 7-13 Sept. 1997, Rev. Sci. Instrum., Vol 69, p 643, 1998
(3) C. Barue, M. Lamoureux, P. Briand, A. Girard and G. Melin, J. App. Phys. 76, p 2662 (1994).
(4) R. Geller, Electron Cyclotron Resonance Ion Sources and ECR Plasmas (Institute of Physics Publishing Bristol and Philadelphia, 1996), p 194.

Presenting Author : Lamoureux M.
Presentation : Oral
Monday 11:00