T. Lokajczyk et al., A SIMPLE METHOD FOR THE MEASUREMENT OF THE ELECTRON-TEMPERATURE IN A HELIUM PLASMA BY MEANS OF LASER ATOMIC-ABSORPTION SPECTROSCOPY, Journal of physics. D, Applied physics, 31(14), 1998, pp. 1706-1711
It is shown that, for plasmas in which electron-atom collisions domina
te over other collision processes, the electron temperature can be der
ived from the density of metastable helium states measured with laser
atomic absorption spectroscopy. The model describing the electron temp
erature as a function of the density of the metastable helium states i
s independent of the electron density and is valid for electron temper
atures T-e= 2-10 eV and for electron densities n(e) less than or equal
to 5 x 10(14) cm(-3) to within an error of 20%. For an extended param
eter range a more complex model, additionally requiring knowledge of t
he electron density, may be used.