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Verification of a fusion neutron diagnostic Bonner sphere spectrometer on measurement of a 241Am–Be neutron source


A Bonner sphere spectrometer (BSS) was developed for neutron diagnostic on HL_2A Tokamak. It contains eight polyethylene spheres embedded with SP9 3He proportional counter. Before setting up on the Tokamak experimental hall, a verification experiment was arranged on a 241Am–Be neutron source to test its spectrometry capability. The neutron response functions were calculated by Monte Carlo code Geant4 to simulate the real measurement environments. By least square method, the neutron spectrum was finally unfolded on log domain from 0.1 eV to 11 MeV. It has a remarkable consistency to the ISO 8529-1 standard 241Am–Be neutron spectrum. This shows that the BSS is effective and reliable for neutron spectrum determination.

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Corresponding author

Correspondence to Jing Cao.

Additional information

This work was supported by the National Natural Science Foundation of China (Nos. 11375195 and 11375263) and National Magnetic Confinement Fusion Science Program of China (No. 2013GB104003).

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Cao, J., Jiang, CY., Yang, QW. et al. Verification of a fusion neutron diagnostic Bonner sphere spectrometer on measurement of a 241Am–Be neutron source. NUCL SCI TECH 27, 128 (2016).

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  • Bonner sphere spectrometer
  • Tokamak
  • HL_2A
  • Geant4
  • 241Am–Be