Neutron leakage spectra benchmark of a spherical polyethylene sample with a²⁵²Cf fission source

【摘要】 This paper presents the development and validation of China’s first benchmark measurement system for neutron leakage time-of-flight（TOF） spectra using a ²⁵²Cf spontaneous fission source and spherical polyethylene sample.EJ-309 and CLYC scintillation detectors were used for neutron detection,and a shadow cone was employed for background suppression.Notably,the SiC detector was,for the first time on this platform,applied as the starttime signal generator in TOF spectrum measurement.The TOF spectrum covering the energy range of 0.15-8.00MeV was measured,and the results were systematically compared with evaluated data from four major nuclear libraries:ENDF/B-Ⅷ.1,JEFF-3.3,JENDL-5,and CENDL-3.2.The comparison revealed strong agreement across the full spectrum,with calculated to experimental（C/E） deviations remaining within 5% in the high-energy region and within 13% at low energies.These results verify the system’s stability and suitability for integral experiments.The established benchmark platform provides a strong technical foundation for future neutron nuclear data validation,particularly in shielding applications and the improvement of fission-spectrum nuclear databases.更多还原

【Abstract】 This paper presents the development and validation of China’s first benchmark measurement system for neutron leakage time-of-flight（TOF） spectra using a ²⁵²Cf spontaneous fission source and spherical polyethylene sample.EJ-309 and CLYC scintillation detectors were used for neutron detection,and a shadow cone was employed for background suppression.Notably,the SiC detector was,for the first time on this platform,applied as the starttime signal generator in TOF spectrum measurement.The TOF spectrum covering the energy range of 0.15-8.00MeV was measured,and the results were systematically compared with evaluated data from four major nuclear libraries:ENDF/B-Ⅷ.1,JEFF-3.3,JENDL-5,and CENDL-3.2.The comparison revealed strong agreement across the full spectrum,with calculated to experimental（C/E） deviations remaining within 5% in the high-energy region and within 13% at low energies.These results verify the system’s stability and suitability for integral experiments.The established benchmark platform provides a strong technical foundation for future neutron nuclear data validation,particularly in shielding applications and the improvement of fission-spectrum nuclear databases.更多还原