System to quantify gamma-ray radial energy deposition in semiconductor detectors

Apparatus for measuring gamma-ray energy deposition for use in conjunction with a semiconductor detector, said detector comprising two electrodes and a detecting material, said detector producing a charge signal E(t) when an incident gamma-ray interacts with said detector, said charge signal having an amplitude corresponding to an amount of energy deposited in said detector by said gamma-ray comprising:

• digitizing means for converting said charge signal E(t) into a digitized charge signal;
• a computational means for receiving said digitized charge signal, for calculating in which of a plurality of zones said gamma-ray deposited energy in said detector, and for having an output indicating an amount of energy deposited by said gamma-ray in each of said zones;
• a pulse conversion means for receiving said charge signal E(t) from said detector and for converting said charge signal E(t) into an amplitude number that is proportional to said amplitude of said charge signal E(t);
• a multi-channel analyzer for defining a plurality of channels corresponding to successive values of said amplitude number, with each of said channels being capable of storing a count, and for receiving said amplitude number from said pulse conversion means;
• and
• a rejection analyzer for analyzing the output of said computational means, for determining whether the output of said computational means indicates a Compton escape event or a full energy event, and for generating a rejection analyzer output signal for being received by said multi-channel analyzer which has a STORE value when a radial energy histogram indicates a full energy event;
• wherein
• said multi-channel analyzer increments said count in said channel corresponding to said amplitude number only when said rejection analyzer output signal has said STORE value.

Apparatus for measuring gamma-ray energy deposition for use in conjunction with a semiconductor detector, said detector comprising two electrodes, a detecting material, and an electric field having electric field lines running through said detector material, said detector producing a charge signal E(t) that varies during a collection period occurring immediately after an incident gamma-ray interacts with said detector material, comprising:

• means for measuring said charge signal E(t) at a plurality of times during said collection period;
• digitizing means for converting said charge signal E(t) into a digitized charge signal;
• and
• a computational means for receiving said digitized charge signal, for calculating a coordinate colinear with one of said electric field lines for locating said gamma-ray interaction, and for calculating an amount of energy deposited at said coordinate.