Sun Particles and Radioactive Decay

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Discussion Overview

The discussion revolves around the potential influence of solar particles on radioactive decay rates, exploring various claims and studies related to environmental effects on nuclear decay. Participants examine the validity of specific research findings and the reproducibility of results in this context.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Exploratory

Main Points Raised

  • Some participants question the relevance of a specific article regarding solar particles and radioactive decay, noting that independent confirmation of the claims made in the article is lacking.
  • There is a discussion about established environmental effects on decay rates, particularly in electron capture, which depend on the electronic environment of the atom.
  • He et al. (2007) claim to have observed a significant change in beta decay rates under certain conditions, but others argue that this effect was not reproduced in subsequent experiments.
  • Jenkins and Fischbach (2008) proposed a correlation between solar influences and alpha decay rates, but later tests reportedly did not support their findings, leading to skepticism about their claims.
  • Participants mention that Jenkins and Fischbach's theories have evolved to include ideas that some find implausible, such as a neutrino-mediated effect from solar flares, which is challenged by the nature of solar flares and neutrinos.
  • Cardone et al. claim to have observed variations in alpha decay rates induced by ultrasound, but these claims are met with criticism regarding the validity of their experimental methods.

Areas of Agreement / Disagreement

Participants express disagreement regarding the relevance and validity of various claims about environmental effects on radioactive decay. There is no consensus on the influence of solar particles or the reproducibility of the studies mentioned.

Contextual Notes

Several claims discussed are based on studies that have not been independently verified, and there are concerns about systematic errors in the experiments cited. The discussion highlights the complexity and uncertainty surrounding the relationship between environmental factors and radioactive decay rates.

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Relevant to what?

This is a result that no independent group has been able to confirm.
 
I don't believe the effect has been reproduced by anyone. If not, then no, it is not really relevant.
 
FAQ: Do rates of nuclear decay depend on environmental factors?

There is one environmental effect that has been scientifically well established for a long time. In the process of electron capture, a proton in the nucleus combines with an inner-shell electron to produce a neutron and a neutrino. This effect does depend on the electronic environment, and in particular, the process cannot happen if the atom is completely ionized.

Other claims of environmental effects on decay rates are crank science, often quoted by creationists in their attempts to discredit evolutionary and geological time scales.

He et al. (He 2007) claim to have detected a change in rates of beta decay of as much as 11% when samples are rotated in a centrifuge, and say that the effect varies asymmetrically with clockwise and counterclockwise rotation. He believes that there is a mysterious energy field that has both biological and nuclear effects, and that it relates to circadian rhythms. The nuclear effects were not observed when the experimental conditions were reproduced by Ding et al.

Jenkins and Fischbach (2008) claim to have observed effects on alpha decay rates at the 10^-3 level, correlated with an influence from the sun. They proposed that their results could be tested more dramatically by looking for changes in the rate of alpha decay in radioisotope thermoelectric generators aboard space probes. Such an effect turned out not to exist (Cooper 2009). Undeterred by their theory's failure to pass their own proposed test, they have gone on to publish even kookier ideas, such as a neutrino-mediated effect from solar flares, even though solar flares are a surface phenomenon, whereas neutrinos come from the sun's core. An independent study found no such link between flares and decay rates (Parkhomov 2010a). Laboratory experiments[Lindstrom 2010] have also placed limits on the sensitivity of radioactive decay to neutrino flux that rule out a neutrino-mediated effect at a level orders of magnitude less than what would be required in order to explain the variations claimed in [Jenkins 2008].

Jenkins and Fischbach's latest claims, in 2010, are based on experiments done decades ago by other people, so that Jenkins and Fischbach have no first-hand way of investigating possible sources of systematic error. Other attempts to reproduce the result are also plagued by systematic errors of the same size as the claimed effect. For example, an experiment by Parkhomov (2010b) shows a Fourier power spectrum in which a dozen other peaks are nearly as prominent as the claimed yearly variation.

Cardone et al. claim to have observed variations in the rate of alpha decay of thorium induced by 20 kHz ultrasound, and claim that this alpha decay occurs without the emission of gamma rays. Ericsson et al. have pointed out multiple severe problems with Cardone's experiments.

He YuJian et al., Science China 50 (2007) 170.

YouQian Ding et al., Science China 52 (2009) 690.

Jenkins and Fischbach (2008), http://arxiv.org/abs/0808.3283v1, Astropart.Phys.32:42-46,2009

Jenkins and Fischbach (2009), http://arxiv.org/abs/0808.3156, Astropart.Phys.31:407-411,2009

Jenkins and Fischbach (2010), http://arxiv.org/abs/1007.3318

Parkhomov 2010a, http://arxiv.org/abs/1006.2295

Parkhomov 2010b, http://arxiv.org/abs/1012.4174

Cooper (2009), http://arxiv.org/abs/0809.4248, Astropart.Phys.31:267-269,2009

Lindstrom et al. (2010), http://arxiv.org/abs/1006.5071, Nuclear Instruments and Methods in Physics Research A, 622 (2010) 93-96

F. Cardone, R. Mignani, A. Petrucci, Phys. Lett. A 373 (2009) 1956

Ericsson et al., Comment on "Piezonuclear decay of thorium," Phys. Lett. A 373 (2009) 1956, http://arxiv4.library.cornell.edu/abs/0907.0623

Ericsson et al., http://arxiv.org/abs/0909.2141
 
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