Abstract
The electron-capture (EC) decay rate of in metallic Cu host and the -decay rate of in the host alloy Al-Au have been measured simultaneously at several temperatures, ranging from 0.350 K to 293 K. No difference of the half-life of between 12.5 K and 293 K is observed to a precision of 0.1%. By utilizing the special characteristics of our double-source assembly, possible geometrical effects that influence the individual rates could be eliminated. The ratio of to activity thus obtained also remains constant for this temperatures range to the experimental precision of . The resulting null temperature dependence is discussed in terms of the inadequacy of the often-used Debye-Hückel model for such measurements.
- Received 12 November 2007
DOI:https://doi.org/10.1103/PhysRevC.77.051304
©2008 American Physical Society