Development of nuclear pumped lasers (NPL) in the CFBR-Ⅱ reactor is briefly reviewed. The results of the two NPL experiments in CFBR-Ⅱ reactor are described. The first one focused on the principle of nuclear pumped ...Development of nuclear pumped lasers (NPL) in the CFBR-Ⅱ reactor is briefly reviewed. The results of the two NPL experiments in CFBR-Ⅱ reactor are described. The first one focused on the principle of nuclear pumped laser, and 4-mW laser output power achieved. The second NPL experiment focused on the small signal gain and the efficiency of the nuclear pumped He-Ar-Xe gas mixture at 1.73 μm. The maximum laser power measured to be 45 mW when thermal neutron flux rate is 6.9 × 1014 cm-2 · s-1. The small signal gain at 1.73 μm by the Rigrod analysis method is to be 0.24%-cm'1, and the saturation intensity is fitted to be 36 W/cm2.展开更多
A biaxial rotational technique is proposed to improve the neutron irradiation uniformity for a large sample,and the theoretical method is established to predict and design the main parameters. The technique used a dev...A biaxial rotational technique is proposed to improve the neutron irradiation uniformity for a large sample,and the theoretical method is established to predict and design the main parameters. The technique used a device to rotate the target sample around two perpendicular axes simultaneously. Numerical calculations found that the lowest common multiple of the two angular speeds should be large enough to improve the uniformity,and the minimal experimental time should be no less than 600 s. For a three-dimensional sample with a size of 20 cm × 12 cm × 14 cm, the maximal non-uniform neutron irradiation factor of the sample is mainly determined by the distance between the center of the sample and of the point neutron source. It was computed to be less than 10% when the distance was no less than 34 cm. Experiments were carried out on the CFBR-II reactor and the experimental results were in good accordance with the theoretical analysis. As a result, the theoretical conclusions given above are reasonable and of reference value for the design of future irradiation experiments.展开更多
文摘Development of nuclear pumped lasers (NPL) in the CFBR-Ⅱ reactor is briefly reviewed. The results of the two NPL experiments in CFBR-Ⅱ reactor are described. The first one focused on the principle of nuclear pumped laser, and 4-mW laser output power achieved. The second NPL experiment focused on the small signal gain and the efficiency of the nuclear pumped He-Ar-Xe gas mixture at 1.73 μm. The maximum laser power measured to be 45 mW when thermal neutron flux rate is 6.9 × 1014 cm-2 · s-1. The small signal gain at 1.73 μm by the Rigrod analysis method is to be 0.24%-cm'1, and the saturation intensity is fitted to be 36 W/cm2.
基金Supported by the National Science Foundation of China(No.11305152)the Science and Technology Development Foundation of CAEP(Nos.2014B0103006 and 2012A0103002)
文摘A biaxial rotational technique is proposed to improve the neutron irradiation uniformity for a large sample,and the theoretical method is established to predict and design the main parameters. The technique used a device to rotate the target sample around two perpendicular axes simultaneously. Numerical calculations found that the lowest common multiple of the two angular speeds should be large enough to improve the uniformity,and the minimal experimental time should be no less than 600 s. For a three-dimensional sample with a size of 20 cm × 12 cm × 14 cm, the maximal non-uniform neutron irradiation factor of the sample is mainly determined by the distance between the center of the sample and of the point neutron source. It was computed to be less than 10% when the distance was no less than 34 cm. Experiments were carried out on the CFBR-II reactor and the experimental results were in good accordance with the theoretical analysis. As a result, the theoretical conclusions given above are reasonable and of reference value for the design of future irradiation experiments.
