R. Denkelmann et al., Measurement of rate coefficients for electron-atom collisions in a helium plasma by laser-induced fluorescence, J PHYS B, 32(19), 1999, pp. 4635-4646
Citations number
28
Categorie Soggetti
Physics
Journal title
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
We present experimentally obtained rate coefficients for electron-atom coll
isions for Delta n = 0 transitions of neutral helium. Results for the dipol
e-allowed transitions 3(3)S-3 P-3, 3 P-3- 3 D-3, 3 S-1-3 P-1, 3 D-1-3 P-1,
4 S-1-4 P-1 and 4 D-1-4 P-1 are given for an electron temperature range of
3-7 eV. For the transitions 3 S-3-3 P-3 and 3 P-3-3 D-3 results down to tem
peratures below 1 eV were obtained. The measurements were performed in a ma
gnetic multipole plasma source by a laser perturbation method. The plasma p
arameters were measured by employing a Langmuir probe. The electron density
was in the range of 10(11) to several 10(12) cm(-3) at helium filling pres
sures of a few Pascal. The results are compared with the theoretical and ex
perimental data available in the literature.