METHOD FOR MONITORING MOVING OBJECTS TO DETECT FISSIONABLE NUCLEAR MATERIALS Russian patent published in 2000 - IPC

FIELD: radiation monitoring. SUBSTANCE: method involves setting desired level of false alarm probabilities (P_fas); measuring background count of neutrons and calculating mean count of neutrons (m) within preset exposure time; calculating operational threshold of alarm ( C ); measuring neutron count within mentioned exposure time with object present in monitored area (m₁); comparing m₁ and C and sending alarm according to results of comparison. According to invention, threshold C is calculated from formula , where k is number of standard deviations from mean value for normal (Gauss) distribution corresponding to desired P_fas; a, b, and d are factors chosen when approximating tabulated data of Poisson distribution. EFFECT: improved consistence between actual probability of false alarms and false alarm setting probability. 1 dwg, 1 ex