Abstract: A method and a system for processing information signals contained in a plurality of contiguous energy bands of a wide band signal generated by photon emission or absorption, such as from a gamma or X-ray source, and containing desired information signals and undesired noise signals. A radiation detector accepts this photon emission and produces position signals and energy signal representative thereof. The method and the system of the present invention consists in directing the position signals in a predetermined ones of a first purality of storage banks corresponding to the contiguous energy bands. The position signals are directed and cumulated into specific ones of the banks as determined by the level of its corresponding energy signal. The relation between accumulated position signals in these banks is evaluated by comparing the signals in each bank with every other ones of the banks and rating said relation of signals between banks.