Experimental study of Stark broadening and shift of the HeI line 41D-21P (lambda=4921 A) and its forbidden component 41F-21P (lambda=4920.35 A) for electron densities 7 x 10 14 <approximately Nsub(e) [cm-3] <approximately 3 x 1016

Measurements of the HeI line 41D-21P,lambda=4921.93 A and its forbidden component 41F-21P,lambda=4920.35 A have been carried out for the electron density range 7x1014< approximately Nsub(e) (cm-3)< approximately 3x1016. The lines were emitted from a continuous He afterglow plasma emerging from a plasmatron device with gas pressures ranging from 100 torr to 2 atm. These results are in general agreement with the measurements of Birkeland et al., Nelson et al., Burgess et al. and Wulff, but not in agreement with the new calculations of Barnard et al. (Auth.)