The critical parameters of the thermal explosion micro hot-spot model dependence on the pulse duration

The dependencies of critical laser initiation energy density of pentaerythritol tetranitrate (PETN) – aluminum nanoparticles, PETN – cobalt nanoparticles and lead azide – lead nanoparticles on pulse duration were calculated in terms of the refined micro hot-spot model. It was shown that the absorption efficiency of the laser irradiation taken into account makes the initiation criterion change. According to the calculation results, the criterion in the limit of short pulses is energy density matching the experimental data. If the neodymium pulses duration is less than 50 ns, the radius of the nanoparticles with highest temperature varies insignificantly. The expression for the critical hot-spot temperature dependence on the pulse duration was derived. The conclusion was made that the model refining with nanoparticles absorption efficiency dependence on their radius is sufficient for the "small particles' paradox" solution.