Measurements of Local Electric Fields in Low Density Plasmas via Stark-Splitting of Hydrogen Resonance Lines
- A. Steiger 2
- K. Grützmacher 2
- C. Pérez 1
- M. I. de la Rosa 1
- J. Seidel 2
-
1
Universidad de Valladolid
info
- 2 Physikalisch‐Technische Bundesanstalt, 10587 Berlin, Germany
ISSN: 0094-243X
Año de publicación: 2002
Tipo: Aportación congreso
Resumen
The aim of this paper is to discuss in detail the schemes for electric field measurements in low density plasmas via Stark‐splitting of the first two hydrogen resonance lines. Beyond it, we have proved by experiment that advanced UV‐laser spectrometers, especially developed for two‐photon spectroscopy of plasmas, are well suited for this purpose. As a first demonstration at low electric fields, simple opto‐galvanic detection was chosen for measuring the Stark‐splitting of the Doppler‐free 1S‐2S and 1S‐3S/D two‐photon transition of atomic hydrogen produced by thermal dissociation in a small reference cell. In addition, we have performed measurements in a hollow cathode discharge which provides higher electric fields in its cathode fall region and the 1S‐2S spectrum was detected spatially resolved by means of an opto‐galvanic signal and polarization spectroscopy as well. Finally, another detection scheme, namely two‐photon induced Balmer‐α fluorescence applied as sheet diagnostic will be described.