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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.
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Barnes et al. (1968) studied this question.
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