^(155)Eu衰变γ射线发射几率的精确测量

Precise measurements of emission probabilities for y-rays from Eu decay

经堆中子辐照过的^(154)Sm样品,用阳离子交换法分离纯化,得到^(155)Eu核素。用4πβ-γ符合法测量放射性活度和用小平面Ge探测器测量^(155)Eu衰变发射的γ光子数,精确测定了γ射线的发射几率。对于强γ射线和弱γ射线的不确定度分别为1.7％和4.5％。与文献报道值相比较,本测量结果明显改善。

Nuclide 155Eu was separated and purified from the 154Sm sample irradiated by the reactor neutrons by using the cation exchange technique. Activities were measured by the 4πβ-γcoincidence method and the γ-ray spectra of 155Eu decay were measured with a small-area planar Ge detector. Emission probabilities of the y-rays were precisely determined, with uncertainties of 1.7% and 4.5% for the strong and weaker y-rays, respectively. The present results have been considerably improved in comparison with previously reported values.