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According to the demands of an array detector in the X-ray pulsar navigation system for Micro-channel Plate (MCP), a selection method for the MCP was explored. Four key parameters for the selection of MCPs, the uniformity of gain, impedance matching, dark count rate and the gain coefficient were determined. Based on the four key parameters, corresponding experiments were designed and the selection process of MCPs was set out. The amplitudes and counting rates of MCPs selected by proposed method were tested. The tested results show that the relative error of each detection unit is not identical. When a single channel anode is used, the ranges of the maximum relative error Δ1i and minimum relative error Δ2i of the amplitudes for output signals from the ith anode are 7%-13.5% and 3%-6.7%, respectively, and when a four-channel anode is used, Δ1i and Δ2i are 7.8% and 3.1%, respectively. Moreover, the relative error between the anode count rate n1+n2+n3+n4 from the single channel and N from the four-channel shared anode is 4.38%, less than 10%. Obtained results indicate that the MCPs with good performance have been effectively chosen by the proposed selection method. ©, 2015, Chinese Academy of Sciences. All right reserved.

With the aim to serve in bad environments and to meet the requirements of real-time and long-term service,a new kind of double parameters and high temperature-pressure fiber Bragg grating(FBG) sensor with a temperature-compensator was put forward.Firstly,the constant elasticity alloy was selected based on the special environments for the sensor.Then,a new kind of structure combined with a circular cylinder and a circular diaphragm was designed by taking the optimized constant elasticity alloy as the substrates.Finally,three experiments of temperature,pressure and temperature-pressure were performed.Experimental results indicate that the sensor not only has great temperature and pressure detection ranges,but also can realize the linear measurement within the ranges of 0~60 MPa and 0~350 ℃.The experiments offer the pressure sensitivities in 0.013 6 nm/MPa,temperature sensitivity in 0.020 1 nm/℃,and the static errors in 0.046% and 0.029%,respectively.These indicators can meet the requirements of practical engineering applications.