method and device for determining the spatial distribution of the surface of a radioactive body emitted electrons.

摘要

The device consists of: a gaseous detector comprising at least one chamber (2) and containing an inert gas and a photon-emitting gas or vapour between two parallel electrodes (3a, 3b) across which a high DC voltage (HT) is applied, a first electrode (3a) being intended to receive against its outer surface the surface of the radioactive body (5, 6) to be observed; a brightness amplifier (13) arranged so as to receive the photons emitted by the excited atoms which are produced near a second electrode (3b) by the electron avalanche due to the electric field between the first and second electrodes; a camera (12) placed behind the brightness amplifier; and a computer (15) suitable for calculating, from the camera output signal, the positions (9) on the first electrode at which the electrons emitted by the said surface of the radioactive body enter the said gaseous detector. IMAGE