DOI: 10.55176/2414-1038-2021-4-5-17
Authors & Affiliations
Bobrovsky T.L., Prusachenko P.S., Khryachkov V.A.
A.I. Leypunsky Institute for Physics and Power Engineering, Obninsk, Russia
 
 
 Bobrovsky T.L. – Research Engineer. Contacts:  1, pl. Bondarenko, Obninsk, Kaluga region, Russia, 249033. Tel.: +7 (900) 571-04-77; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
  Prusachenko  P.S. – Researcher.
  Khryachkov V.A. – Research Director, Dr. Sci. (Phys.-Math.).
Abstract
Machine learning  is one of the leading directions in digital signal processing. For example, in  neutron spectrometry, artificial neural networks are actively used to suppress  gamma background when analyzing signals from scintillation detectors. This  article describes a method for determining the quality of n/γ-separation by an  artificial neural network. The efficiency of the method is demonstrated by  analyzing the signals obtained by measuring the prompt neutron spectrum of 252Cf  spontaneous fission using a scintillation detector  based on a stilbene crystal. The essence of the method is to determine the  proportion of falsely identified events for each of the analyzed signal classes  using a known reference method. An exemplary gamma-ray source was used to  determine the false count of recoil protons. This approach made it possible to  estimate the fraction of events from electrons identified as recoil protons and  the fraction of recoil protons perceived as electrons, depending on the light  yield of the scintillation signal. This, in turn, made it possible to reconstruct  the true energy spectra for different types of particles, including for the  region of low signal amplitudes, where the separation quality is usually poor.  The reconstructing error was less than 8 % for the light yield  region of less than 120 keVee.
Keywords
 artificial neural  networks, pulse shape separation, scintillation detector, n/γ separation,  stilbene, classification, Keras, separation parameter, mixed radiation fields,  neutron spectrometry 
Article Text (PDF, in Russian)
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UDC 539.1
Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2021, issue 4, 4:1