低温金属环境中^198Au半衰期的测量  

Measurement of ^(198)Auβ^--Decay Half-Life in Metal Au at Low Temperature

作　　者：曾晟[1] T. Spillane F. Raiola C. Rolls 

机构地区：[1]中国原子能科学研究院核物理研究所,北京102413 [2]鲁尔大学,鲁尔44780

出　　处：《原子能科学技术》2009年第6期481-484,共4页Atomic Energy Science and Technology

基　　金：国家重点基础研究发展计划资助项目(G200077400);国家自然科学基金资助项目(10375096,10575137,10575136)

摘　　要：利用德国鲁尔大学DTL实验室的中子源,通过197Au(n,γ)198Au反应得到198Au@Au样品,在室温(T=293 K)和低温(T=12 K)条件下交替测量金属Au环境中198Au的412 keV特征γ射线,通过分析得到不同温度下198Au的半衰期。实验结果表明,与文献值T1/2=(2.694 3±0.000 8)d相比,T=293 K时198Au的半衰期变长(0.4±0.7)%;T=12 K时变长(4.0±0.7)%。这一变化趋向与德拜等离子体模型的预言相符,但其幅度显著小于模型的估计值。The ^198Au@Au sample was produced via ^197Au（n,γ）^198Au reaction. The relative activities of 412 keV characteristic γ-ray from the ^198Au@Au sample were measured at room temperature T=293 K and low temperature T= 12 K, alternately. The β^- - decay half-life of ^198Au in Au metallic environment was observed to be longer by （0.4±0.7）% at T=293 K and by （4.0±0.7）% when the metal was cooled to T= 12 K, both compared to the literature value of T1/2 = （2. 694 3±0. 000 8） d. The result is consistent qualitatively with, but clearly lower than, the prediction of the Debye plasma model.

关 键 词：β-衰变半衰期 金属环境 温度效应 德拜等离子体模型 

分 类 号：O571.423[理学—粒子物理与原子核物理]