Neutral radiation detection and localization

A imaging process for detecting and localizing incident X or soft gamma radiations comprising the steps of

• subjecting a body of gas to said radiations through a pin hole collimator under conditions which result in electron formation upon absorption of the radiations by the gas;
• drifting the electrons toward a photon production space by an electric field;
• subjecting said photon production space to an electric field of sufficient value to produce secondary photons by excitation of atoms of said gas in said space by said electrons;
• detecting the formation of said secondary photons and determining the location of such formation;
• detecting the light event associated with each said electron formation and measuring time elapsed between said light event and the secondary photon formation 31.

An imaging system for determining the distribution of neutral radiation from a source, comprising:

• a gas filled enclosure having an input window impervious to light and transparent to said radiation and an output window transparent to light, the atoms of said gas being adapted to produce photoelectrons by interaction with said neutral radiation;
• collimator means for location on the path of said radiation between said source and input window;
• parallel electrode means transparent to said radiation, located in said enclosure and associated with electric supply means for defining in said enclosure an interaction and electron drift space and a secondary photon production space, said electrode means and electrical supply means being arranged for drifting the electrons formed in the interaction space to the secondary photon production space;
• a layer of wavelength shifter material on said output window;
• and detection means associated with said layer for simultaneously localizing the light emitting events in said layer and determining their intensity.