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Radioactive Decay Apparently Influenced By the Sun 267

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."
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Radioactive Decay Apparently Influenced By the Sun

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    • Re:Repost of (Score:5, Informative)

      by b4dc0d3r ( 1268512 ) on Saturday September 01, 2012 @02:43PM (#41200751)

      It's not a repost. That story was about predicting solar flares based on the hypothesis presented here.

      They were posted out of order, certainly, and this one is about 2 weeks too late, and offers no value over the previous story.

      But this is a better article about the underlying experiments, even though the website waited until today to push it out. Slow news day at WaveWatching.net? Or is this just pimping an old story for blog views?

      It's worse than a dupe, and you calling it a repost does not properly insult the report.

      • Actually, they were posted in the correct order but then the sun messed up space-time so that they arrived out of order.

    • by quax ( 19371 )

      Ups, wan't aware of thtat when I submitted this. At least there is some additional info in this article i.e. the more detailed graphs from the research and the video. Although not the most captivating speaker the presentation adds interesting details to extend that they think they see patterns specific to the core of the sun.

      If this pans out it could actually open up the possibility of neutrino telescopy. That'll be extremely exciting.

    • Re:Repost of (Score:5, Informative)

      by bcrowell ( 177657 ) on Saturday September 01, 2012 @09:16PM (#41202975) Homepage

      It's not exactly the same, but it is the same kookery warmed over. Here's a summary.
      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. [Ding 2009]
      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]. Despite this, Jenkins and Fischbach continue to speculate about a neutrino effect in [Sturrock 2012]; refusal to deal with contrary evidence is a hallmark of kook science. They admit that variations shown in their 2012 work "may be due in part to environmental influences," but don't seem to want to acknowledge that if the strength of these influences in unknown, they may explain the entire claimed effect, not just part of it.
      Jenkins and Fischbach made further claims in 2010 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.
      In agreement with theory, high-precision experimental tests show no detectable temperature-dependence in the rates of electron capture[Goodwin 2009] and alpha decay.[Gurevich 2008]
      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 [arxiv.org], Astropart.Phys.32:42-46,2009
      Jenkins and Fischbach (2009), http://arxiv.org/abs/0808.3156 [arxiv.org], Astropart.Phys.31:407-411,2009
      Jenkins and Fischbach (2010), http://arxiv.org/abs/1007.3318 [arxiv.org]

  • This is exciting (Score:5, Insightful)

    by cunniff ( 264218 ) on Saturday September 01, 2012 @02:19PM (#41200623) Homepage

    Possibly the most exciting physics news of the year. Although the detection of the Higgs boson was big, it mostly confirmed what existing theory predicted. Interesting, important - but, to some physics, perhaps a bit boring.

    If further measurements continue to verify this effect, there are some very interesting new physics to discover.

    • by cunniff ( 264218 )

      but, to some physics, perhaps a bit boring.

      Err, make that, "but, to some *physicists", perhaps a bit boring."

    • I second that. Here we are looking at more sophisticated effects of the weak force by solar neutrinos. This is exciting indeed!
    • Re:This is exciting (Score:5, Informative)

      by volsung ( 378 ) <stan@mtrr.org> on Saturday September 01, 2012 @03:08PM (#41200891)

      This argument about solar influence on nuclear decay rates has been going on for a few years now. The experimental issues are hard to interpret, because you have to be able to rule out external influences on your counting apparatus. It is extremely hard when the period of your signal matches the orbit of the Earth, which aliases all sorts periodic behavior that has nothing to do with new physics. There are seasonal variations in temperature, cosmic rays, the voltage delivered by the power company, foot traffic near your lab, etc, etc. Verifying that none of these things can possibly influence your results is what takes all the time.

      A semi-random selection of earlier papers on the subject:

      "Experimental investigation of changes in beta-decay count rate of radioactive elements" (1999):
      Claiming 24 hour and 27 day periodicities in the decay rates of cobalt-60 and cesium-137
      http://arxiv.org/pdf/hep-ex/9907008v1.pdf [arxiv.org]

      "Power Spectrum Analyses of Nuclear Decay Rates" (2010):
      Reports of an annual periodicity in the decay rates of chlorine-36, silicon-32, manganese-56, and radium-226.
      http://arxiv.org/abs/1007.0924 [arxiv.org]

      "Solar Influence on Nuclear Decay Rates: Constraints from the MESSENGER Mission" (2011)
      A study of cesium-137 decay rates on a spacecraft going to Mercury show no change as the spacecraft travelled closer to the Sun.
      http://arxiv.org/abs/1107.4074 [arxiv.org]

      "Search for the time dependence of the 137Cs decay constant" (2012)
      Cesium-137 decays in a detector underground (shielding it from most cosmic rays) show no significant periodicity, with limits much lower than claimed signals.
      http://arxiv.org/abs/1202.3662 [arxiv.org]

      "Power Spectrum Analysis of LMSU (Lomonosov Moscow State University) Nuclear Decay-Rate Data: Further Indication of r-Mode Oscillations in an Inner Solar Tachocline" (2012)
      Studies of strontium-90 decays show a variety of periodic variations, ranging from 0.26 per year to 3.96 per year.
      http://arxiv.org/abs/1203.3107 [arxiv.org]

      This list goes on and on. There is hardly any consensus on the issue.

      • Many thanks for the very interesting links.

        We learned that decay rates were random, but with a certain statistical mean.

        Often in science 'random' is a word for 'we don't know yet how'. Finding out how is really the fun part. Now that there is some sort of link to solar radiation and decay rates, we can be closer to seeing how decay rates might not be so random but even predictable.
        • Re:This is exciting (Score:5, Informative)

          by volsung ( 378 ) <stan@mtrr.org> on Saturday September 01, 2012 @03:42PM (#41201063)

          I think the problem is that the link is not yet established. What we have is a link between count rates in a detector observing a sample of some isotope and time of year, which no one disputes (we reasonably assume they are not making up their data). The argument is whether you can make the inductive leap to the claim that radioactive decay rates depend on the amount of solar radiation. As shown in some of those papers above, other experiments don't (like the test with the MESSENGER probe) show the effect you would expect if solar radiation were the cause.

          Even if we do find there is an external influence on decay rates (which would be pretty nifty), that definitely does not imply that the times of individual radioactive decays are predictable.

          • Perhaps we could run an experiment simultaneously on the Moon, on Mars, and a few other places throughout the Solar System, and compare the effects of their positions to the Earth-bound ones. If indeed radioactive decay can be externally sped or slowed, we might be able to invent power plants or nuclear-waste disposers far beyond our current imagination.
          • I think the problem is that the link is not yet established. What we have is a link between count rates in a detector observing a sample of some isotope and time of year, which no one disputes (we reasonably assume they are not making up their data). The argument is whether you can make the inductive leap to the claim that radioactive decay rates depend on the amount of solar radiation. As shown in some of those papers above, other experiments don't (like the test with the MESSENGER probe) show the effect you would expect if solar radiation were the cause.

            Apparently there are some other papers that cast doubt on the basic finding. See the comment by "AK" at http://wavewatching.net/2012/09/01/from-the-annals-of-the-impossible-experimental-physics-edition/ [wavewatching.net]

            That comment also points out that this "second study" includes one of the authors of the first study, so it's not really an independent confirmation.

            And the first plot at that link (the original study) doesn't - IMO - actually look very supportive: the average period is about right, but the phase isn't very s

      • by quax ( 19371 )

        It seems to me there is enough accumulated oddity to follow up with some space based measurements in order to get a better signal to noise ration and eliminate some possible systematic error sources.

      • by ceoyoyo ( 59147 )

        You missed the one where they found a seasonal variation just like this one, but it disappeared when they looked at the ratio of counts for two different elements. The rest of the paper is an analysis of the seasonal variations of their detectors.

        I don't have the reference with me, but someone else will probably post it. These guys have notably NOT done the simple experiment of monitoring both Cl and one of the elements they insist don't respond.

  • Claim not new (Score:5, Informative)

    by JoshuaZ ( 1134087 ) on Saturday September 01, 2012 @02:22PM (#41200639) Homepage
    The original claim dates from 2008 and 2009. (Original paper here- http://arxiv.org/abs/0808.3283 [arxiv.org]). While TFA claims that this has been confirmed, the group confirming this shares many of the same authors http://arxiv.org/abs/1205.0205 [arxiv.org]. This still has not yet been confirmed by a genuinely independent group. Also the claims still only focus on two specific isotopes Si-32 and Ra-226. One thing worth emphasizing is that this has no bearing on things like the age of the Earth or other uses of radiometric dating. The isotopes are not used generally for radiometric dating and the percentage change in decay rates being observed is tiny. Moreover, for many of the sorts of things we do radiometric dating we have multiple distinct methods that cross-check each other. For example, when doing zircon dating, one can date from both the decay of U-238 and that of U-235 which use distinct decay changes. This may turn out to be some very interesting thing going on, but as of right now the impact is limited even if it is correct.
    • Re:Claim not new (Score:5, Informative)

      by Mt._Honkey ( 514673 ) on Saturday September 01, 2012 @02:39PM (#41200725)

      Yeah. There were also come claims with Cl-36, but multiple measurements have the effect in opposite directions and different magnitudes (http://arxiv.org/abs/1208.4357 [arxiv.org], so they seem more likely to be due to instrumentation effects than real differences

      This is one of those "extraordinary evidence" things, and we aren't there yet. Annual variation is always suspect because experimental conditions can change subtly with the weather.

    • Re:Claim not new (Score:5, Interesting)

      by quax ( 19371 ) on Saturday September 01, 2012 @02:40PM (#41200735)

      Well, this is a different data series so I still think it's fair to say that the second study confirms the original finding, although further completely independent confirmation is highly desirable.

      Also noteworthy: This apparently only affects beta decay i.e. it seem to hint at an unknown reaction involving the weak force only.

      The video goes into some more detail, revealing that they found periodicities that are typical for the core of the sun, only neutrino interaction could account for that.

  • makes sense, there's probably something from the sun that interacts with a nucleus inducing a slightly higher rate of decay.

    If you think about what a particle accelerator is, we basically fling particles at other particles and induce a (in many cases artificial or otherwise bizarre) form of radioactive decay. If you figure every particle has some interaction cross section with gamma rays from the sun you will then have an observable effect as the sun cycles. You can probably produce the same effect with a

    • by Teancum ( 67324 )

      It may make some logical sense, but this is a mechanism that has not been previously observed and largely discounted as insignificant by experimenters in the past.

      The one thing that is known to be coming from the Sun that pretty much can't be isolated from other items (by going deep underground and trying to rule out other environmental factors) would be neutrinos and neutrino flux. This was mentioned above, but there are some interesting implications if that has some significant impact.

      Neutrinos are usual

      • by Sir_Sri ( 199544 )

        but this is a mechanism that has not been previously observed and largely discounted as insignificant by experimenters in the past.

        Well, except that if it is what I think it is, it has been observed experimentally even in nuclear physics, it's how you can use lasers for Uranium enrichment, and the effect is definitely there in electron structures. Granted, me being wrong would pose some really interesting science, and sticking numbers to it properly is a lot harder than typing a few sentences on /..

        And the effect is insignificant, so that makes sense. Relativity still applies to an object moving 1m/h but it's not all that important.

  • by WindBourne ( 631190 ) on Saturday September 01, 2012 @02:37PM (#41200715) Journal
    I wonder if Mars was subjected to more radiation if its core would spin more?
  • Neutrinos? (Score:5, Interesting)

    by rrohbeck ( 944847 ) on Saturday September 01, 2012 @02:41PM (#41200739)

    If neutrinos are the suspects, wouldn't it be easy to measure the decay rates of one of those nuclei in a strong neutrino flux, close to a large nuclear reactor or in a neutrino beam from an accelerator?

    • Re:Neutrinos? (Score:5, Informative)

      by quax ( 19371 ) on Saturday September 01, 2012 @03:04PM (#41200875)

      This would be a good follow up. But producing a high flux of neutrinos is not trivial especially the right kind. The current thinking is that there are three types of neutrinos and that the latter change via a process called neutrino oscillation on the way from sun to earth.

      http://en.wikipedia.org/wiki/Neutrino_oscillation [wikipedia.org]

      • Re:Neutrinos? (Score:5, Interesting)

        by volsung ( 378 ) <stan@mtrr.org> on Saturday September 01, 2012 @03:54PM (#41201145)

        Since you mention neutrinos, it is also worth noting that there was similar discussion (5 or so years ago) as to whether we can observe periodic variation in the number of neutrinos seen on Earth using various experiments. (Note that periodicities in neutrino rates are not what physicists call "neutrino oscillations". That's an entirely different effect.) Those papers claiming a periodicity included one of the authors on this study of radioactivity decay, and the analysis techniques were disputed by other papers as giving an unacceptably high rate of false positives. The experiments presented counter-analyses showing no significant signal once the probability of false positives was dealt with. (Disclaimer: I was tangentially involved in one of those papers.)

        I haven't looked closely enough at the radioactive decay papers to see if the same issue has cropped up again here, but the neutrino periodicity argument is a good example of how these signals can fall apart under closer scrutiny.

        • by quax ( 19371 )

          It'll be great if you could take the time to scrutinize these papers. If this is simply due to erroneous data analysis this deserves to be shut down.

      • My first thought would be to launch a satellite. Farther away from the sun = less neutrinos.

    • Yes, something very similar to this has been done:

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

      It puts 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 by Jenkins and Fischbach in 2008. And yet Jenkins and Fischbach are still speculating that the effect they claim

  • Now M.I.A. is controlling radioactive decay? That's one powerful finger.
  • by Animats ( 122034 ) on Saturday September 01, 2012 @02:52PM (#41200805) Homepage

    Interesting. The effect is well under 1%, but above the noise threshold. Observed for radium (a beta emitter) but not europium (an alpha emitter), with the same experimental setup.

    Although heat, pressure, and chemical binding have no measurable effect on radioactive decay, external particles hitting an atom certainly can affect radioactive decay. That's how chain reactions and particle accelerators work.

    There's a suspicion here that solar neutrinos might be responsible. Beta decay involves the weak nuclear force, while alpha decay involves the strong nuclear force. Neutrinos are known to interact with the weak nuclear force.

    The Fermilab accelerator, which can be used as a neutrino generator, was shut down and decommissioned in September 2011. That would have provided a way to test this hypothesis.

  • In the year 2013, the world learned it was wrong to fear Mother Earth. For all along, watching and judging humanity through the eyes of it's radioactive minions was


  • For all we know about sub atomic particles and forces this was something not in the least predicted.

    What if another reaction within the sun could cause massive decay all over the earth? Periods of mass extinction or mass mutation.

    On the practical side it hints that decay rate can be controlled. Could be really important for subatomic particle researchers trying to produce and observe particles with ridiculously short life spans.

    If the effect could be produced on demand within a localized area for long perio

  • If the element is so full of neutrons that they are already flying off in all directions, wouldn't that giant supermega generator (You can see it in the sky on a clear day) spewing googlians of subatomic particals have some effect? (As in the spewed partials would be adding energy to the already very dense atoms) If I could test this I would measure the decay as a mass of a very dense element was moved closer to the sun. Sorry didn't read the arcticle maybe this was covered :-)
  • It's a artefact of the detector, as in some unknown effect radiating from the sun is affecting the reading.
  • by macraig ( 621737 ) <[moc.liamg] [ta] [giarc.a.kram]> on Saturday September 01, 2012 @04:26PM (#41201341)

    If this is truly confirmed, then the obvious next step is to determine what particles being emitted by the sun are causing this effect. Is it a neutrino thing? Neutrinos aren't affected by the magnetosphere at all, IIRC. Once we know the particle(s) involved, there might be some useful tech emerge from it; perhaps it could be used to build a new generation of fission reactors where this effect can be used to enhance control or safety? I dunno... it's not my field at all but that seems obvious enough.

  • If we're moving closer or farther from the Sun, shouldn't the differences in gravity make time flow at different speeds?

  • From most to least plausible order:

    Random accidental correlation that cannot be repeated in independent experiments

    Detector noise caused by Sun.

    Solar neutrinos catalyze decay.

    Undiscovered particles (dark matter) interaction catalyzes decay.

    Gravity affects decay rates differently than relativity predicts.

    Gravity affects clocks differently than relativity predicts.

  • It is hard to see how anything having to do with neutrinos could be effected by whatever local noon is in a lab in Isreal. Look at the time of day correlations.. If I did this in a lab in the US should I expect the same time of day results? If so how would such results square with the earth being transparent to neutrinos? Would this not be evidence against neutrinos as a cause?

    Separatly it is hard to see how the paper gets away with voltage and temperature measurements which correlate so closely with th

  • bad experiment (Score:5, Interesting)

    by drolli ( 522659 ) on Saturday September 01, 2012 @06:58PM (#41202251) Journal

    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.

  • by manu0601 ( 2221348 ) on Saturday September 01, 2012 @10:38PM (#41203329)

    Nuclear disintegration is the weak interaction at work.

    The weak interaction involves neutrinos.

    The sun emits a lot of neutrinos.

    Of course, it is not that simple, and physicists still have to churn out a theory. But the idea that the sun can influence nuclear disintegration does not looks odd to me

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