LASER INDUCED UNDERWATER SPARKS

Abstract
Measurements have been taken of the radiative flux density, the spectrum, and the temporal behavior of laser induced underwater sparks. When a 30‐MW Q‐switched ruby laser was focused into water, the resulting spark revealed a blackbody‐like spectrum with a temperature of 15 000°K. The spark was delayed in time by 15 nsec with respect to the laser pulse and had a temporal behavior very similar to the laser pulse producing it.