| Along with the development of manned space flight which is heading form short-term to long-term, the damage of space neutron radiation has become a factor that can not be ignored, more and more attention has been paid to the detection of space neutron. Long scintillation detectors and data acquisition system has been set up for space neutron at our laboratory. In this paper, time resolution, position resolution and energy response of the detector have been analyzed according to the off-line data.The off-line data, such as the time, position and integral charge which are readout from the digitizer have been analyzed based on the dual-ended characteristic. The time difference between the dual-ended signals has been chosen to find the true events from the off-line data. The results show that: the true events can be extracted effectively and the interference of background can be restrained obviously with a reasonable coincidence window.Combining with the experiment, the generation, transmission and collection of the light in the scintillator have been simulated by Monte Carlo. The results show that time difference between the dual-ended signals is linear with the position of the radiation particle. Therefore, on the base of coincidence measurement, the position response can be obtained by the time difference of true events. A time resolution of 0.9 ns was reached resulting in the position resolution of 12 cm and the relative position resolution of 9.6% which have reached the same level as foreign technology.The integral charge of the dual-ended signals of the detector changes with not only the energy but also the position of the radiation particle. So the geometrical mean QGM of the dual-ended signals has been used to calibrate the energy while QGM is proportional to the energy and almost independent of position. The energy calibration has been done via the Compton edge of 60 Co source,137 Cs source and the natural 40 K,208Tl. The energy response is linear. |
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