RESEARCHES OF THE PROPERTIES OF MATERIALS USED FOR PROTECTION FROM NEUTRON RADIATION USING BONNER SPHERE SPECTROMETER WITH A 3He-COUNTER

Abstract

The energy and pulse height spectrums after passage of neutron radiation through samples of materialsmost often used to protect against neutron radiation (paraffin, paraffin with boric acid, paraffin with boric acid and lead, polyethylene, polyethylene with boron and boron carbide) are measured using a PuBe neutron source using a NEMUS spectrometer on Bonner spheres with 3He -counter. The values of linear attenuation coefficients and neutron relaxation lengths in these materials, neutron spectra for these materials are given. The percentage of neutrons in the energy subbands is determined according to the radiation weighting factor. The neutron flux density, the ambient dose equivalent power, the absorbed dose rate in the neutron radiation air, the transition coefficients from the neutron fluence to the ambient dose equivalent and average neutron radiation energy are measured. Calculation of energy spectrum, basic characteristics of neutron radiation and extended uncertainties is performed by the MAXED (maximum entropy and deconvolution), applying the Bayes theorem, method using the UMG_3.3 software.

Keywords

• protection from neutron radiation
• linear neutron attenuation coefficient
• neutron relaxation length in the material
• neutron radiation spectrum
• neutron flux density
• ambient dose rate equivalent
• absorbed dose rate
• NEMUS spectrometer on Bonner spheres