Nuclear material detection method

Abstract

A method for detecting photonuclear-induced delayed neutrons emitted from a material by exciting the material with high-energy photon stimulation to generate neutrons emissions, detecting said neutrons, generating electric pulse signals representative of detected neutrons, amplifying and shaping said electric pulse signals with an amplifier, low-pass filter and high-pass filter, and comparing said amplified and shaped electric pulse signal with a threshold voltage to generate output pulses to detect delayed neutrons.

1 . A method for detecting delayed neutrons emitted from a material, said method comprising: 
 exciting said material with high-energy photon stimulation to generate neutron emissions photonuclear techniques; and    detecting whether delayed neutrons are emitted from said material as a result of said exciting, said detecting comprising: 
 generating electric pulse signal representative of detected neutrons;  
 amplifying said electric pulse signals;  
 shaping the electric pulse signals with a low-pass filter and a high pass filter to eliminate noise due to a photon flash event and thereby create well defined electric pulse signals;  
 comparing pulses generated from the high-pass filter to a threshold voltage and generating output pulses when pulses from the high-pass filter exceeds the threshold voltage;  
 monitoring the output pulses to detect delayed neutrons.  
   
   
   
       2 . The method of  claim 1  wherein the electric pulse signals representative of detected neutrons have a pulse rise time of approximately 0.5 microseconds.  
   
   
       3 . The method of  claim 1 , wherein the step of detecting whether delayed neutrons are emitted from said material as a result of said exciting of the material occurs within microseconds of an accelerator-produce, photon flash event.  
   
   
       4 . The method of  claim 1 , further comprising buffering the generated output pulses to five-volt-pulses to make the output TTL compatible.  
   
   
       5 . (canceled)