Detection of neutrons - using superconducting-normal state transition by radiation emitted when neutron is absorbed, giving good spatial resolution

摘要

Method of detecting neutrons makes use of the phenomenon of transition of grains or homogeneous films of a superconductive material towards the normal state under the effect of a photor or a charged particle emitted when the neutron is absorbed by a material. The appts. incorporates a neutron receptor comprising a medium which absorbs neutrons and emits electromagnetic radiation or a charged particle, and grains or a film of superconducting material. Specifically, the receptor includes a cryostat to maintain the superconducting material below the critical temp., and a means of creating a magnetic field of specific value to maintain the material in the superconducting state in the absence of radiation. A circuit measures a quantity or a change in a quantity associated with the state of the material to detect the transition of the material from the superconducting state towards the normal state, e.g. change in resistivity, magnetic permeability or magnetic flux. Method is efficient and gives good spatial resolution.