Application of surface barrier solid state ionization chambers to measurements on fission

Abstract

Abstract Gold-silicon surface barrier detectors ∼ 3 4 ″ in diameter have been made and used in several experiments on the fission process: (1) A pair of detectors, with detecting surfaces parallel and facing each other at a distance comparable with their diameters and with U235 deposited on one detector, has been used to measure the mass distribution in fission with thermal neutrons for several values of the total kinetic energy of the fragments. Values as high as 500 to one for the ratio of asymmetric to symmetric fission were obtained. (2) A similar arrangement, but including a third detector, was used for the measurement of the mass distribution in ternary fission. (3) The ratio of ternary to binary fission for U235 fission with thermal neutrons was determined. (4) The variation of the fission cross section of U233 with energy was measured for neutron energies in the range 6 eV to 19 eV. The usefulness of solid state detectors and their superiority over most other types of known detectors for these measurements is clearly evident.