Continuous emission of plasma in the soft X-ray region
The limits of the soft X-ray region are not very well defined. They are characterised by a strong absorption in air and poor reflectivity on all surfaces except at grazing incidence. This means that it is necessary to work in vacuum and that imaging is made difficult. Plasma sources of soft X-radiation include high voltage vacuum spark, sliding spark, theta- and z-pinches, tokamaks, laser produced plasma and stellar objects. One of the applications of continuous soft X-radiation is in the diagnostics of laboratory and stellar plasmas. The electron occupation of the discrete levels of the atoms in a plasma often show strong deviations from that in thermal equilibrium, whereas the occupation of the continuous levels is well approximated by that in thermal equilibrium. In such cases, it is advantageous to use the continuous emission of the free electrons for diagnostic purposes. This paper is concerned with the continuous emission of plasma in the soft X-ray region. The experimental set-up for soft X-rays is presented, in particular the focussing of the soft X-rays, the spectrometer for the X-rays and the different X-radiation detectors. Finally, three types of sliding sparks in vacuum are described.
Bibliographic Reference: Extract: Proceedings of the 2nd workshop on Plasma and Laser Technology, Cairo (1990) pp. 213-251
Availability: Forschumgszentrum Jülich GmbH (KFA), Jülich (DE)
Record Number: 199110526 / Last updated on: 1994-12-02
Original language: en
Available languages: en