19 research outputs found
Evidence for Solar Influences on Nuclear Decay Rates
Recent reports of periodic fluctuations in nuclear decay data of certain
isotopes have led to the suggestion that nuclear decay rates are being
influenced by the Sun, perhaps via neutrinos. Here we present evidence for the
existence of an additional periodicity that appears to be related to the Rieger
periodicity well known in solar physics.Comment: Presented at the Fifth Meeting on CPT and Lorentz Symmetry,
Bloomington, Indiana, June 28-July 2, 201
Analysis of environmental influences in nuclear half-life measurements exhibiting time-dependent decay rates
In a recent series of papers evidence has been presented for correlations
between solar activity and nuclear decay rates. This includes an apparent
correlation between Earth-Sun distance and data taken at Brookhaven National
Laboratory (BNL), and at the Physikalisch-Technische Bundesanstalt (PTB).
Although these correlations could arise from a direct interaction between the
decaying nuclei and some particles or fields emanating from the Sun, they could
also represent an "environmental" effect arising from a seasonal variation of
the sensitivities of the BNL and PTB detectors due to changes in temperature,
relative humidity, background radiation, etc. In this paper, we present a
detailed analysis of the responses of the detectors actually used in the BNL
and PTB experiments, and show that sensitivities to seasonal variations in the
respective detectors are likely too small to produce the observed fluctuations
Additional experimental evidence for a solar influence on nuclear decay rates
Additional experimental evidence is presented in support of the recent
hypothesis that a possible solar influence could explain fluctuations observed
in the measured decay rates of some isotopes. These data were obtained during
routine weekly calibrations of an instrument used for radiological safety at
The Ohio State University Research Reactor using Cl-36. The detector system
used was based on a Geiger-Mueller gas detector, which is a robust detector
system with very low susceptibility to environmental changes. A clear annual
variation is evident in the data, with a maximum relative count rate observed
in January/February, and a minimum relative count rate observed in July/August,
for seven successive years from July 2005 to June 2011. This annual variation
is not likely to have arisen from changes in the detector surroundings, as we
show here.Comment: 8 pages, 6 figure