Pulsation of 10 and 20 emission from laser-produced plasmas. I. Experiment

Abstract

We report measurements on time-resolved spectra of the 20 (and, indirectly, 10) emission from plasmas produced by focusing 70400-psec duration Nd-laser pulses to intensities above 1014 W/cm2 onto planar targets. We observe repeated bursts of the emission lasting only 1020 psec and typically separated by 3050 psec. During these bursts the emitted frequency was observed to sweep rapidly across the wavelength band (50 A wide), indicating the operation of processes that modulate the emission via phase. The results support our previous work [Dragila, Maddever, and Luther-Davies, Phys. Rev. A 36, 5292 (1987)], where we concluded that such phase modulation must occur in order to explain the observation that time-integrated spectra obtained in the same conditions were modulated. Show more