Thomson scattering in a low-pressure argon mercury positive column

The electron density and the electron temperature in a low-pressure argon m ercury positive column are determined using Thomson scattering. Special att ention has been given to the stray light reduction in the Thomson scatterin g setup. The results are obtained in a discharge tube with a 26 mm diam, 5 mbar of argon, a mercury pressure in between 0.14 and 1.7 Pa, and an electr ic current ranging from 200 to 400 mA. The systematic error in the electron density is 15%, the statistical error is 25%. The total error in the elect ron temperature is 10%-20%. (C) 2000 American Institute of Physics. [S0021- 8979(00)02820-6].