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Scientists Confirm Nuclear Decay Rate Constancy

Posted by timothy on from the was-just-the-one-time-I-swear dept.

As_I_Please writes "Scientists at the US National Institute of Standards and Technology and Purdue University have ruled out neutrino flux as a cause of previously observed fluctuations in nuclear decay rates. From the article: 'Researchers ... tested this by comparing radioactive gold-198 in two shapes, spheres and thin foils, with the same mass and activity. Gold-198 releases neutrinos as it decays. The team reasoned that if neutrinos are affecting the decay rate, the atoms in the spheres should decay more slowly than the atoms in the foil because the neutrinos emitted by the atoms in the spheres would have a greater chance of interacting with their neighboring atoms. The maximum neutrino flux in the sample in their experiments was several times greater than the flux of neutrinos from the sun. The researchers followed the gamma-ray emission rate of each source for several weeks and found no difference between the decay rate of the spheres and the corresponding foils.' The paper can be found here on arXiv. Slashdot has previously covered the original announcement and followed up with the skepticism of other scientists."

2 of 95 comments (clear)

  1. Why wouldn't the scientists in this study... by Anonymous Coward · · Score: 0, Troll

    Use the same isotopes (manganese-54, silicon-32, and radium-226) that were in the original studies?

    Because by using gold-198 they aren't validating their claim that radioactive decay itself is uninfluenced by neutrino exposure, only that gold-198's radioactive decay is likely unaffected by neutrino exposure.

    It would seem then that they're purposely avoiding replicating the original studies parameters, perhaps to avoid observing the same phenomenon.

    1. Re:Why wouldn't the scientists in this study... by Anonymous Coward · · Score: 0, Troll

      Call me naive, but maybe they had better reasons not to use the same material.

      All right, you're naive. As far as I can tell, the OP comment is still valid. How can they invalidate the orginal experimenter's experiment unless they try to replicate the original experiment?

      First experimenter: "We observed this phenomenon in manganese-54, silicon-32, and radium-226."

      Second experimenter: "We did not observe that phenomenon in gold-198 therefore you are wrong."

      Of course, once they (potentially) validate the original experiment and observe the same phenomenon is gold-198 (showing that gold-198 is sensitive to the same phenomenon), then using foil and spheres made out of gold-198 to test sensitivity to neutrino flux is a clever idea.