Detonation of PETN single crystals initiated by an electron beam

Luminescence in the volume of PETN (tetranitropentaerytrite) single crystals exposed to an electron beam (duration 20 nsec) with an energy density of 15 J/cm$^2$, which exceeds the threshold of explosive decomposition, was investigated in real time. Exposure to the ionizing pulse causes radioluminescence and emission related to the critical electron emission from a dielectric which is transformed to a vacuum discharge. The emission zone propagates from the surface into the vacuum at a speed of 5000–6500 m/sec. The absorption of electron beam energy in the irradiated layer (0.25 mm) causes the formation and propagation of a shock wave enhanced by the chemical reaction in the crystal. When the shock wave is reflected from the target on the rear side of the sample, its amplitude increases. This leads to detonation accompanied by emission which propagates from the backside to the irradiated surface of the sample at a speed of 7500–8500 m/sec with the subsequent expansion of the explosive decomposition products into the vacuum.