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[en] A pulsed fission neutron measurement system running in current mode was put forward by using an encapsulated scintillating fibre array (ESFA). The system is composed of a neutron collimator, an ESFA, a bundle of light guide, a photomultiplier tube, a high voltage supply and an oscilloscope. The study shows that the sensitivity range of the scintillation detector for 1 MeV neutron is from 10^-10 to 10^-16 (A·cm²·s/n). The detector sensitivity for 1 MEv neutron is about nine times greater than that of the gamma ray with the same energy. Hence, the detector can be used to measure the pulsed fission neutron of flux from 108 to 1016 (n/cm²·s) and duration up to several microsecond. The detector discrimination power for gamma rays can be improved by adding lead in front of it

[en] In the present work, a new type neutron detecting system is reported, which can absolutely measure neutron parameters in n + γ mixed fields and has a long continuance of static high vacuum of 10^-4 Pa. The detecting system, with middle neutron-detecting sensitivity, short time response and big linear current output, has applied successfully in pulsed neutron beam measurement

[en] The medium-type fast-neutron detector responds to direct neutron irradiation and it has an extreme effect on its design and practical applications. Monte-Carlo simulation programs based on Geant4 toolkit are developed to study the neutron direct radiation response sensitivity of the medium-type fast-neutron detector. The emission of the charged heavy particles of commonly used materials of detector's sensitive unit due to neutron incidence is simulated. The result shows that the selection of the materials of the charge collector, the threshold absorber and the rear isolator directly affect on the response sensitivity of neutron direct radiation. The response sensitivity of neutron direct radiation contributes about 6% to the total neutron sensitivity in the present sensitive unit which uses a graphite sensitive collector and Teflon threshold absorber and rear isolator. An improved structure of sensitive unit using high resistance graphite as the material of the threshold absorber and a rear isolator instead of Teflon is discussed, which can effectively reduce the response sensitivity of neutron direct radiation. (authors)

[en] A new scintillating-fiber-array neutron detector has been developed. The detector consists of a bee-hive-shaped lead absorber, a scintillating fiber array, a light guide, a filter and a photomultiplier tube. The experimental results show that the new detector's neuron-to-gamma sensitivity ratio is improved about six times compared to traditional plastic scintillation detectors to 2.5 MeV neutrons and 1.25 MeV gamma rays. Hence, the detector should be very useful in the measurements of pulsed neutrons from fission reactions in a neutron-gamma mixed field

[en] Efficiency-enhanced Si PIN detector and high-sensitivity, large-area Si PIN detectors array has been developed and their sensitivity and relative error have also been simulated comprehensively. According to the theoretical study, the following two results can be obtained. Efficiency-enhanced Si PIN detectors can improve the sensitivity greatly. In comparison with the single intensified Si PIN detector, the detectors array has higher sensitivity. High-sensitivity, large-area Si PIN detectors array can be used to detect the γ rays of extraordinarily low flux

[en] Based on the computer image processing technique, the waveform digitalization system for analogue oscillograph film has been developed. The system can accurately extract and recognize the waveform curve from complicated background, and the coordinate data of waveform can be saved. In this paper, the hardware structure and principle, software module, image processing pivotal arithmetic and technique are introduced in detail. The typical waveform films have been recognized and digitalized, the results indicate that the waveform digitalization system has the excellent character of high recognized precision, speed and automatization. (authors)

[en] The manufacture technology of GaAs semi-insulator detectors are introduced in details. The leakage current, time response, γ-ray response and proton sensitivity are measured. The simultaneous input-output measurement system in continuous proton pulse experiments are also introduced and the results of the measurement are analyzed as well

[en] The physical theory of Compton Scattering Imaging (CSI) is described, and the physical model of a CSI system is developed. In the mean time, the feasibility of this system used in Non-destructive Testing is studied by Monte Carlo method. The results prove that the iron block can be discriminated from concrete using this imaging system. This simulation method can be used in the study, design and improvement of CSI systems

[en] Background: To measure gamma ray in pulsed radiant hybrid field of gamma ray and neutron, the detector system is required to have a very fast time response, and a good γ/n discrimination. Purpose: The aim is to do experimental study on the detector of Cherenkov plumbic-glass fiber matrix sensitive to gamma ray. Methods: Based on the Cherenkov radiant theory, simulation calculation of energy deposition of the gamma, neutron in fiber arrays materials was done by using MCNP. According to the calculation data, plumbic-glass was selected as Cherenkov scintillated optical fiber, combining with the material of gathering and transmitting scintillated light, the photomultiplier (PMT), we designed detector of Cherenkov plumbic-glass fiber matrix sensitive to gamma ray. And then the 14.1-MeV neutron sensitivity experiments are performed on the Cockcroft-Walton generator in China Institute of Atomic Energy, the 1.25-MeV gamma sensitivity experiments on ⁶⁰Co source in Northwest Institute of Nuclear Technology. Results: The experimental γ/n discrimination is about 42.3 at incident angle of 45°, which is accord basically with the result of simulation calculation. Conclusion: The detector system has high γ/n discrimination, which can fulfill the requirements for gamma ray measurement in pulsed radiation hybrid field. (authors)