多普勒能移反冲距离法测核寿命的技术

An apparatus for nuclear lifetime measurement with recoil-distance Doppler-shift method

自行研制了多普勒能移反冲距离法测量寿命的装置，对装置的性能作了测试，并首次在国内用于核实验。用３１Ｐ轰击９３Ｎｂ靶测得了１２０Ｘｅ基带能级寿命及１２１Ｃｓ和１１７Ｉ的部分能级的寿命。实验结果表明，用多普勒能移反冲距离法能测量１０－１２－１０－９ｓ范围核激发态寿命。

The recoil-distance Doppler-shift (RDDS) methods is an accurate and direct method to measure lifetime of nuclear levels in 10-12-10-9s range. An apparatus based on the RDDS method was designed and tested. An in-beam experiment with the apparatus was first performed in China. Lifetimes were measured for the levels of 120Xe ground band and a few levels of 121Cs and 117I which are produced by bombardment on 93Nb target with 31p beam.