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Radioactive Decay Apparently Influenced By the Sun
quax writes "In school you probably learned that the decay rate of radioactive matter is solely determined by the halftime specific to the element. There is no environmental factor that can somehow tweak this process. At least there shouldn't be. Now a second study confirmed previous findings that the decay rate of some elements seems to be under the subtle and mysterious influence of the sun. As of now there is no theoretical explanation for this strange effect buried in the decay rate data."
Disclaimer: i am an experimental physicist from another field (with experience in precision measurements).
looking at the arxiv preprint:
Why would one allow a +-3% variation in *absolute* temperature (figure 6). 6% of 300K are 18K (this is huge. My experiment needed to be recalibrated when the temperature changed by 1 degree). This explains also the *huge* fluctuation of the biasing voltage "lead accumulator" completely propotional to the temperature. which brings me to the next point: the paper makes is sound like this voltage was used *without further stabilization* for biasing the electronics. Why any sane experimentalist would accept such fluctuations when cheap and reliable means (controlled heater, 50cent voltage controller) is beyond my comprehension.
That being said, we talk about some difference on the order of 500 counts (per day, see the paper and multiply the numbers...), respectively 25 per hour or 1 per 2 minutes. I am no expert on it, but at such low count rates an exclusion of the influence of cosmic rays would be needed. Sasly the paper also does not show any dark count rate experiment. If they let the same detector run without anything inside and show the data, then we could make some conclusions.
Ideally they shoud have run an identical detector without a sample in close vincinity at the same time and correlate the fluctuations.