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A high dynamic range calorimeter has been designed for the DArk Matter Particles Explore(DAMPE) satellite. It consists of 308 BGO crystals, multi-dynode readout PMTs and front end electronics system. We have built on previous research to show that BGO fluorescence should not be saturated by high electron energy density under DAMPE's energy range. A BGO fluorescence simulator is set up to calibrate the energy range of the dynodes, while a cosmic-ray unit is used to calibrate 1 MIP with the ADC count in dynode 8. Linearity is achieved for the dynamic range from 0.5 MIPs to 1.26×105MIPs. The requirements of DAMPE can thus be satisfied. 相似文献
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A two dimensional multi-wire proportional chamber with delay line readout was developed, which has a large sensitive area of 30 cm× 30 cm. Two cathode planes using printed circuit boards are orthogonally placed to give two coordinates of the impact point of the particle. Signals collected from the cathode strips are amplified and discriminated from two ends of the delay line at each cathode board. By recording the time difference between the two discrimination pulses and the common gate pulse from anode wires, a coordinate position was reconstructed, and a position resolution of better than 1 mm could be obtained in the whole sensitive area along the anode wires. 相似文献
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近年来,磁流变抛光作为一种确定性加工方法已成为获得高精度非球面的重要手段。作者以回转对称二次抛物面为例,分析了磁流变抛光中使用抛光轮校正工件位置的理论方法,并通过实验在Φ230 mm熔石英样件上验证对刀理论,分别在X方向和Y方向以少于3次的调整次数校正工件位置,实现了X方向、Y方向偏置量均低于0.009 mm;采用磁流变抛光技术对工件进行了修形实验验证,加工后面形精度RMS由λ/7收敛至λ/40。实验结果表明:作者提出的非球面工件位置对刀校正方法简单、可靠,能够很好地对工件进行精确定位,利于高精度非球面磁流变抛光加工。 相似文献
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衍射光学元件较球面、非球面光学元件在校正色差方面具备较大优势,尤其是在红外光学领域,应用衍射光学元件可进一步增加光学系统的设计自由度。随着红外光学市场的进一步增大,常规的衍射光学金刚石车削技术难以满足大规模需求,精密模压技术成为解决上述问题的关键技术。模具设计是实现精密模压的重点,为了缩减模具设计周期,该文采用有限元仿真方法对模具进行预先设计及补偿,并试加工。采用单站式精密模压机对设计的模具进行了精密模压试验。模压试验结果表明:采用合理的工艺参数,能够实现衍射光学元件面形精度PV达到0.56 μm,位置误差<0.011 mm,环带高度误差<0.12 μm,验证了仿真预先补偿在衍射光学模具设计中的有效性。 相似文献
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The particle acceptance instead of the G-factors has been introduced for a particle telescope. The particle acceptance of a telescope module TEST is simulated by using the GEANT4 Monte-Carlo package. The results are presented and explained. 相似文献
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The magnetic characteristics of R5610A-01 photomultiplier tubes are studied in this paper. The experimental data shows that the gain of R5610A-01 loses about 53% when the magnetic field is 3 Gs along its +X axis. A cylinder of one-layer permalloy strip is able to reduce the effect of a 3 Gs magnetic field on the PMT gain to less than 1%. 相似文献
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