NARROW-BAND EXTREME-ULTRAVIOLET LASER-RADIATION TUNABLE IN THE RANGE 90.5-95-NM - APPLICATION TO THE SPECTROSCOPY OF N2

Tunable, narrowband extreme ultraviolet radiation in the range 90.5-95 nm with only limited intensity variations is produced by frequency-tr ipling ultraviolet light from a frequency-doubled dye laser in a gas-j et of xenon. Acetylene gas is found to be an efficient medium for thir d-harmonic generation in this wavelength range as well. The extreme-ul traviolet radiation is applied in a spectroscopic study of the b1PI(u) , nu = 6-8 and nu = 10-12, o1PIu, nu = 0 and b'1SIGMA(u)+, nu = 9 stat es of molecular nitrogen. From linewidth measurements a value k(p) = 6 x 10(10) s-1 for the predissociation rate of the b1PI(u), nu = 11 sta te is deduced.