No evidence for antineutrinos significantly influencing exponential beta(+) decay

作者：de Meijer R J^*; Blaauw M; Smit F D

来源：Applied Radiation and Isotopes, 2011, 69(2): 320-326.

DOI：10.1016/j.apradiso.2010.08.002

• Radioactivity
• Beta decay
• Decay constants
• Solar neutrinos
• Geoneutrinos
• Reactor antineutrinos

High-precision measurements were conducted on the time evolution of gamma-ray count rates during reactor-on and reactor-off periods to investigate the possible influence of antineutrinos on nuclear decay. This experiment was triggered by a recent analysis (Jenkins et al., 2009) of long-term measurements suggesting a possible link to variations in nuclear decay rate and solar neutrino flux. The antineutrino flux during reactor-off periods is mainly due to geoneutrinos and four orders of magnitude lower than during reactor-on periods. No effects have been observed for the two branches in the decay of Eu-152 and the decay of Cs-137, Mn-54 and Na-22. The upper limit determined of the ratio Delta lambda/lambda for Na-22 is (-1 +/- 2) x 10(-4), and Mn-54 is (-1 +/- 4) x 10(-4). In comparison to the interpretation of Jenkins et al. our measurements do not show any such effect to at least two orders of magnitude less. Hence either the hypothesis of Jenkins et al. is not true or else one of two rather unlikely possibilities must also be true: either the effect of neutrinos on beta(-) decay differs considerably from the effect of antineutrinos on beta(+) decay, or the effect of antineutrinos on beta(+) decay must be identical to their effect on beta(-) and electron-capture decay.

• 出版日期2011-2