A real-time Bonner sphere spectrometer(BSS)has been developed for spectral neutron measurements with the HL-2A Tokamak.To correct and verify the accuracy of the neutron spectrum from the BSS,the BSS system was calibra...A real-time Bonner sphere spectrometer(BSS)has been developed for spectral neutron measurements with the HL-2A Tokamak.To correct and verify the accuracy of the neutron spectrum from the BSS,the BSS system was calibrated using monoenergetic neutron beams in the energy range of 100 keV–5 MeV.The response function of the BSS was corrected based on the calibration results,and the corrected BSS system was verified by unfolding monoenergetic neutron spectra.Fusion neutron spectra on the HL-2A have been obtained from the calibrated BSS system for the first time.展开更多
A Bonner sphere spectrometer(BSS) was developed for neutron diagnostic on HL_2A Tokamak.It contains eight polyethylene spheres embedded with SP9~3 He proportional counter.Before setting up on the Tokamak experimental ...A Bonner sphere spectrometer(BSS) was developed for neutron diagnostic on HL_2A Tokamak.It contains eight polyethylene spheres embedded with SP9~3 He proportional counter.Before setting up on the Tokamak experimental hall,a verification experiment was arranged on a^(241)Am–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 from0.1 e V to 11 Me V.It has a remarkable consistency to the ISO 8529-1 standard^(241)Am–Be neutron spectrum.This shows that the BSS is effective and reliable for neutron spectrum determination.展开更多
In order to make further studies on fusion neutron diagnosis on HL-2A /HL-2M,we have developed and succeeded in the calculation of the Response Function for a Bonner sphere spectrometer,which consists of eight polyeth...In order to make further studies on fusion neutron diagnosis on HL-2A /HL-2M,we have developed and succeeded in the calculation of the Response Function for a Bonner sphere spectrometer,which consists of eight polyethylene spheres with ^3He proportional counters inside.The response function of the Bonner spectrometer to neutrons is of fundamental importance for its neutron spectrum unfolding procedure and is directly related to the quality of the unfolded spectrum.In this paper,we calculated the response function to neutrons from 10^-9 MeV to100 MeV by Geant4.In order to test the accuracy of the Geant4 simulation,we apply it to measure an ^241Am-Be neutron source,and the measured neutron counts of the spectrometer and simulated counts are found to be highly consistent,with a relative error up to 9.3%.This has proven the calculation of the neutron response of the Bonner sphere spectrometer by Geant4 to be quite accurate.展开更多
The extended Bonner sphere spectrometer （EBSS） at the HL-2A tokamak for the neutron spectrum is described. This device was developed on the basis of previous Bonner sphere spectrometry （BSS）, aiming to obtain a mo...The extended Bonner sphere spectrometer （EBSS） at the HL-2A tokamak for the neutron spectrum is described. This device was developed on the basis of previous Bonner sphere spectrometry （BSS）, aiming to obtain a more accurate neutron spectrum in the HL-2A tokamak hall. The previous BSS contained eight Bonner spheres （BS）. This EBSS contains 13 3He-filled detectors embedded in polyethylene spheres （PS）, pre-amplifiers, and a parallel processing data acquisition system （DAQ）. A response matrix is simulated in Geant4 taking the effect of the environment into account.展开更多
基金supported by the National Natural Science Foundation of China(Nos.11375195 and 11575184)
文摘A real-time Bonner sphere spectrometer(BSS)has been developed for spectral neutron measurements with the HL-2A Tokamak.To correct and verify the accuracy of the neutron spectrum from the BSS,the BSS system was calibrated using monoenergetic neutron beams in the energy range of 100 keV–5 MeV.The response function of the BSS was corrected based on the calibration results,and the corrected BSS system was verified by unfolding monoenergetic neutron spectra.Fusion neutron spectra on the HL-2A have been obtained from the calibrated BSS system for the first time.
基金supported by the National Natural Science Foundation of China(Nos.11375195 and 11375263)National Magnetic Confinement Fusion Science Program of China(No.2013GB104003)
文摘A Bonner sphere spectrometer(BSS) was developed for neutron diagnostic on HL_2A Tokamak.It contains eight polyethylene spheres embedded with SP9~3 He proportional counter.Before setting up on the Tokamak experimental hall,a verification experiment was arranged on a^(241)Am–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 from0.1 e V to 11 Me V.It has a remarkable consistency to the ISO 8529-1 standard^(241)Am–Be neutron spectrum.This shows that the BSS is effective and reliable for neutron spectrum determination.
基金supported by National Natural Science Foundation of China(Nos.10976028,11375195)National Magnetic Confinement Fusion Science Program of China(No.2013GB104003)
文摘In order to make further studies on fusion neutron diagnosis on HL-2A /HL-2M,we have developed and succeeded in the calculation of the Response Function for a Bonner sphere spectrometer,which consists of eight polyethylene spheres with ^3He proportional counters inside.The response function of the Bonner spectrometer to neutrons is of fundamental importance for its neutron spectrum unfolding procedure and is directly related to the quality of the unfolded spectrum.In this paper,we calculated the response function to neutrons from 10^-9 MeV to100 MeV by Geant4.In order to test the accuracy of the Geant4 simulation,we apply it to measure an ^241Am-Be neutron source,and the measured neutron counts of the spectrometer and simulated counts are found to be highly consistent,with a relative error up to 9.3%.This has proven the calculation of the neutron response of the Bonner sphere spectrometer by Geant4 to be quite accurate.
基金supported by National Natural Science Foundation of China (No. 11375195, No. 11575184)the National Magnetic Confinement Fusion Energy Development Research (2013GB104003)
文摘The extended Bonner sphere spectrometer （EBSS） at the HL-2A tokamak for the neutron spectrum is described. This device was developed on the basis of previous Bonner sphere spectrometry （BSS）, aiming to obtain a more accurate neutron spectrum in the HL-2A tokamak hall. The previous BSS contained eight Bonner spheres （BS）. This EBSS contains 13 3He-filled detectors embedded in polyethylene spheres （PS）, pre-amplifiers, and a parallel processing data acquisition system （DAQ）. A response matrix is simulated in Geant4 taking the effect of the environment into account.
