SUPERCONDUCTING NUCLEAR PARTICLE DETECTOR.
ATOMICS INTERNATIONAL CANOGA PARK CALIF
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Work was undertaken to determine the feasibility of using thin superconducting films as nuclear particle detectors. The results of experiments show conclusively that such devices can be used to detect such radiation. The diffusion of energy from electrons excited by charged particle bombardment was studied by observation of superconducting-normal transitions caused by alpha particles incident on thin films of tin or indium. Because the films were sufficiently narrow, alpha particles initiated transitions across the full width. The transitions were observed by means of the IR drop produced by a transport current. For low current densities, self-terminating pulses were observed. For higher current densities, a normal region initiated by an alpha particle spread by boundary propagation to the ends of the film as the result of Joule heating. The films were deposited on 18-in.-thick crystalline quartz or glass substrates in a vacuum of the order of 0.000001 torr. Superconducting-normal transitions were observed with the films cooled by a liquid helium bath on the back side of the substrate. A thin Po210 source, suspended in vacuum above the film, supplied 5.3 MeV alphas. Author
- Nuclear Instrumentation