ANALYSIS OF BETA-DECAY RATES FOR Ag108, Ba133, Eu152, Eu154, Kr85, Ra226, AND Sr90, MEASURED AT THE PHYSIKALISCH-TECHNISCHE BUNDESANSTALT FROM 1990 TO 1996

• Published in: The Astrophysical journal Vol. 794; no. 1; pp. 42 - 6
• Main Authors: Sturrock, P. A., Fischbach, E., Jenkins, J.
• Format: Journal Article
• Language: English
• Published: 10.10.2014
• Subjects: Annual variations; Compatibility; Counting; Decay rate; Detectors; Rejection; Standard deviation
• ISSN: 1538-4357; 0004-637X; 1538-4357
• DOI: 10.1088/0004-637X/794/1/42

We present the results of an analysis of measurements of the beta-decay rates of Ag108, Ba133, Eu152, Eu154, Kr85, Ra226, and Sr90 acquired at the Physikalisch-Technische Bundesanstalt from 1990 through 1995. Although the decay rates vary over a range of 165 to 1 and the measured detector current varies over a range of 19 to 1, the detrended and normalized count rate measurements exhibit a sinusoidal annual variation with amplitude in the small range 0.068%-0.088% (mean 0.081%, standard deviation 0.0072%, a rejection of the zero-amplitude hypothesis) and phase-of-maximum in the small range 0.062-0.083 (January 23 to January 30). In comparing these results with those of other related experiments that yield different results, it may be significant that this experiment, at a standards laboratory, seems to be unique in using a 4[pi] detector. These results are compatible with a solar influence, and do not appear to be compatible with an experimental or environmental influence. It is possible that Bal33 measurements are also subject to a non-solar (possibly cosmic) influence.