LASING ON A WEAK INTERCOMBINATION TRANSITION (4P(4)S(3 2)-]4S(2)P(3/2)) IN ARII/

Argon laser lines in the violet-blue spectral region have been studied experimentally. CW generation has been achieved on a set of close lin es: 438.4, 437.6, 437.1 and 436.2 nm, the 438.4 and 436.2 nm being obs erved for the first time. CW lasing has been also observed on 418.2 an d 431.0 nm lines. The highest output appeared on the 438.4 nm line, wh ich corresponds to weak quartet-doublet transition 4p(4)S(3/2)-4s(2)p( 3/2). The measurements yielded the Einstein coefficient, branching coe fficient, saturation parameter and unsaturated gain of 438.4 nm transi tion. The study shows the possibility of high power generation on a fo rbidden transition with Einstein coefficient 10(6) sec(-1), the latter being by 1-2 orders lower than for other strong laser lines.