APPARATUS AND METHOD FOR NEUTRON DETECTION BY CAPTURE-GAMMA CALORIMETRY

摘要

FIELD: physics.;SUBSTANCE: invention relates to an apparatus for detecting neutron radiation, preferably thermal neutrons, comprising at least one first section (102) with a high neutron absorption capability and at least one second section (101) with a low neutron absorption capability. The second section comprises a gamma ray scintillator, the gamma ray scintillator material comprising an inorganic material with an attenuation length shorter than 10 cm, preferably shorter than 5 cm for gamma rays of 5 MeV energy in order to provide high gamma ray stopping power for energetic gamma rays in the second section, where the material of the first section is selected from a group of materials, releasing the energy transferred in the first section by neutron capture mainly via gamma radiation, and where the second section surrounds the first section such that a substantial portion of the first section is covered by the second section, the apparatus further comprising a light detector (103) 1, optically connected to the second section in order to detect the amount of light in the second section, the apparatus further comprising an evaluation device connected to the light detector. Said device is able to determine the amount of light, detected by the light detector for one scintillation event, that amount being in a known ratio to the energy transferred by gamma radiation in the second section, where the evaluation device is configured to classify detected radiation as neutrons when the measured total gamma energy E (sum) is above 2.614 MeV.;EFFECT: high accuracy of detecting neutrons.;45 cl, 6 dwg