From the Annals of the Impossible (Experimental Physics)

Updated below.

Photons only slowly emerge from the Sun's core. Neutrinos just pass through once produced.

Radioactive decay is supposed to be the ultimate random process, immutably governed by an element's half life and nothing else.  There is no way to determine when a single radioactive atom will spontaneously decay, nor any way to speed-up or slow down the process.  This iron clad certainty has always been the best argument of opponents to conventional nuclear fission power generation, as it means that the inevitable nuclear waste will have to be kept isolated from the biosphere for thousands of years (notwithstanding recent research attempts at stimulated transmutation of some of the longer lasting waste products.)

When plotting the activity of a radioactive sample you expect a graph like the following, a smooth decrease with slight, random variations .

Detected activity of the 137Cs source. The first two points correspond to the beginning of data taking. Dotted lines represent a 0.1% deviation from the exponential trend. Residuals (lower panel) of the measured activity to the exponential fit. Error bars include statistical uncertainties and fluctuations.

(This graph stems from a measurement on the Beta decay of 137CS and was taken deep underground).

What you don't expect are variations that follow a discernible pattern in the decay rate of a radioactive element, nor any correlation with outside events. But this is exactly what Jere H. Jenkins et al. found:

Plot of measured 36Cl decays taken at the Ohio State University Research Reactor (OSURR). The crosses are the individual data points, and the blue line is an 11-point rolling average. The red curve is the inverse of the square of the Earth–Sun distance. (Error bars are only shown for a limited number of points).

And now this surprising result of the sun's influence has been corroborated.

The latest research was a collaboration of Stanford and Purdue University with the Geological Survey of Israel, rather reputable research power-houses that make these results difficult to dismiss. Their paper contains the following contour graph for the  measured gamma decay during the day plotted over several years. When comparing this with the same kind of graph of the sun's inclination during the observed date range the correlation is quite obvious:

Gamma measurements as a function of date and time of day. The
color-bar gives the power, S , of the observed signal (top).
Solar elevation as a function of date and time of day. The color-bar
gives the power, S , of the observed signal (bottom).

There is a video talk on this phenomenon available online.  It takes some patience to sit through, but gives a more complete picture in explaining how these observed patterns can be correlated to the the Sun's core activity with surprising accuracy.

The evidence for the reality of this effect is surprisingly good, and that is rather shocking. It does not fit into any established theory at this time.

Update and Forums Round-Up

This was the second blog post from this site that has been picked up on slashdot (this was the first one). Last time around WordPress could not handle the load (dubbed slashdot effect). Subsequently I installed the W3 Total Cache plug-in. So before getting back to the physics, I want to use this space to give them a big shout-out.  If you operate a WordPress blog I can highly recommend this plug-in.

This article received almost 30,000 views over two days, the resulting discussions fleshed out some great additional information, but also highlighted what can be easily misread or misconstrued. Top of the list was the notion that this might undermine carbon dating.  For all practical purposes, this can be categorically ruled out. For this to have a noticeable effect, this phenomenon would have to be much more pronounced.  The proposed pattern is just slightly outside the error bars and only imposes a slight variation on top of the regular decay pattern.  Archaeologists should not lose sleep over this. An unintended side-effect was that this attracted creationists. If you adhere to this belief please don't waste your time commenting here.  This is a site dedicated to physics, and off-topic comments will be treated like spam and deleted.

Another source of confusion was the difference between induced radioactive reactions and spontaneous decay. The latter is what we are supposed to see when measuring the decay of a radioactive isotope in the lab and this is what these papers address. Induced transmution is what can be observed when matter is, for instance, irradiated with neutrons.  This process is pretty well understood and happens as a side effect within nuclear reactors (or even a nuclear warhead before the fission chain reaction overwhelms all other neutron absorption).  The treatment of nuclear waste with a neutron flux is what I hinted at in the last sentence of the first paragraph.  This emerging technology is very exciting and merits its own article, but it is an entirely different story. The news buried in the papers discussed here is that there may be a yet unknown neutrino absorption reaction influencing decay rates that were believed to be only governed by the half-life time interval.  At this point an inverse beta decay is known to exist, but the reaction rate is much smaller than what is required to explain the phenomenon that these papers claim.

The spontaneous decay of a radioactive isotope is regarded as the gold standard for randomness in computer science, and there are some products that rely on this (h/t to Dennis Farr for picking up on this).  I.e. if the decay rate of a lump of radioactive material is no longer governed by the simple function $ N(t) = N_0 2^{-t/t_{1/2}} $ then the probability distribution that these random number generators rely on is no longer valid (the decay constant used in the distribution function at the link relates to the half-life time via $  t_{1/2} = \frac{\ln 2}{\lambda} $.

There were various thoughtful critical comments on the methodology and experimental set-up. The most prominent point that came up was the contention that this was essentially the outcome of data-mining for patterns and then hand-picking results that showed some discernible patterns.  Ironically, this approach is exactly the kind of data processing that spawned a billion dollar industry catering to the commercial Business Intelligence market.  To me, this actually looks like a pretty smart approach to get some more mileage out of old data series (assuming the authors didn't discard results detrimentally opposed to their hypothesis). The downside of this is the lack of information on the care that went into collecting this data in the first place.  I.e. it was repeatedly pointed out that experimenters should run a control to capture the background radiation and needed to understand and control for the environmental impact on their measuring devices. Relying on third party data means also relying on the reputation of the researchers who conducted the original experiments.

When the original claims were made they triggered follow-up research. Some of it was inconclusive, some of it contradicted the findings and a measurement performed on the Cassini probe's 238Pu thermonuclear fuel clearly ruled out any sun-distance related influence on that alpha emitter.

Inevitably with controversial results like this the old moniker that "extraordinary claims require extraordinary proof" is repeatedly dragged out.

I always thought this statment was cut off a bit short and should really read: "Extraordinary claims require extraordinary proof and merit extraordinary attention."

Because without the latter, sufficient proof may never be acquired even if it is out there. The experiments required to test this further are not expensive. An easy way to rule out seasonality it to perfom these measurements closer to the equator or have them performed at the same time in a north and south American lab as one slashdot poster suggested.

Ultimately, a Beta emitter measurement on another space probe could lay this to rest and help to conclusively determine if this is a real effect.  It would be very exciting if this can be confirmed but it is certainly not settled at this point.

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96 Responses to From the Annals of the Impossible (Experimental Physics)

  1. Dennis Farr says:

    We have nuclear-powered satellites in orbit at a large range of distances from the Sun. If any of these depend on beta decay for power generation, we should be able to get additional data points quickly. If not we should try this out in space as soon as possible.

    • Ralf says:

      … or next to a nuclear reactor or in a neutrino beam from an accelerator.

    • Kiko says:

      No, this is not possible, these measurements where taken into NO radioactive noise locations. Using the same source and making the measurement in a long period, in a controlled enviroment.

      Outter space is just the opposite. You have neutro, proton, and lot of radiation making not possible this kind of measumement.

      • Ian says:

        You could measure the fluctuations in and/or the drop-off rate of the power output of the RTG, and compare that to the theoretical power drop-off curve.

      • Xander says:

        The cosmic background would presumably be uniform though, and therefore could be accounted for at varying distances. The neutrino flux form a source capable of being treated as a point source, such as the sun, would definitively drop off at i/d2.

        I support a new probe to look at this. I wouldn’t be surprised if beta decay, and even positron decay, are mediated by impact with neutrinos.

        If a probability of interaction is governed by flux intensity, that easily explains the ‘random’ nature of decay. By analyzing the varying beta decay rates of a range of isotopes, such as Cs137 and I131 there might be some new sorting out to do as to how those different nucleonic and orbital configurations might influence the probability of weak field interaction. (Which I conject is cosmic billiards of neutrino to nuclei)

    • Geoff says:

      Nuclear-powered anything rely on nuclear fission, which is an entirely different process from beta decay. Additionally, the fission in nuclear reactors is stimulated by a neutron flux (i.e., it isn’t a standard radioactive decay process).

      • Phil says:

        Actually, many satellites and space probes are powered by thermoelectric generators driven by the heat generated in the nuclear beta decay of isotopes such as Plutonium 238.

        Some of the Russian satellites used small fission plants, I think

    • Craig says:

      It’s been done:
      http://arxiv.org/abs/0809.4248v1
      and the short answer is that there is no correlation of decay with spacecraft distance from the sun.

      • Henning Dekant says:

        Cassini’s thermonuclear reactor uses Pu-238. The latter only has an alpha decay channel. This is supposed to only affect the weak force facilitated Beta decay.

  2. Simon says:

    The odd bit of neutrino catch and release (for want of a better name for it) with the quanta of an unstable element is quite likely to result in additional gamma ray emissions instead of just a normal neutrino being emitted or your regularly scheduled amount of radiation being given off.

    I’m sure they’d find a corresponding increase in beta particle emissions from an appropriate source if they tested that in the same manner, only proportionally less given the vastly higher mass-energy (momentum?) of an electron (eV/s) compared to that of a photon in the gamma spectrum despite the vastly higher speed of the near zero mass-energy photon (eV/(c squared)).

    What they’d also find is that the neutrino waves propagating through the source involved have been absorbed in the situation and are the cause of the lack of steady state in radioactive material in general.

    Incidentally we should be able to detect the reduction in decay rate of reactors in probes far away, with things like the voyager probes having slightly higher masses of their radioactive sources than expected, but simultaneously having a reduction in output.

    • Dennis Farr says:

      This is worth investigating if it holds any promise for controlling the speed of radioactive waste decay, and also because radioactive decay is considered to be the gold standard for a cryptographically random process.

      • Henning Dekant says:

        Dennis, your points are very well taken. The fact that radioactive decay is considered a cryptographic resource in computer science is why I worded my first sentence this way (“ultimate random”).

        If this were to pan out I think Beta-emitters will need to be black-listed for this purpose.

        As to radioactive waste control, there is some promising research conducted that uses particle accelerator technology to create a neutron beam that can induce transmutation. Probably more practical than trying to use neutrinos. The latter are just notorious for not interacting much with matter. Even if this effect pans out and was neutrino induced, you’d probably need to create an immensely intense neutrino flux to have a real impact. Neutron’s will win that technological race hands down.

  3. ED says:

    If this turns out to be an unknown mass-mass interaction, we might get rid of dark matter too.

  4. Eric Albers says:

    This result is expected, what do you mean its not?

    The curvature of spactime varies as the distance to the sun varies, the decay rate is a function of spacetime curvature of course.

    This is well known, really. Just think of space curvature as a density delta, and radioactive decay as being more stable in high density vs less stable in a lower density spacetime.

    You can easily calculate the rate of decay change from Einsteins equations.

    • Henning Dekant says:

      I think you are confusing this with the well know phenomenon that time slows down in a gravity well.

      Very different effect that has no bearing here.

    • Mark H. says:

      Relativistic effects can’t be the cause of this because the radioactive sample and the clocks used to measure the decay rate are in the same reference frame (namely, Earth). As the Earth moves closer to and farther from the Sun, the radioactivity and clocks would both be affected by spacetime curvature in the same way, leading to identical results at all times. This result, should it pan out, has to be some sort of particle interaction.

      • Steve says:

        > Relativistic effects can’t be the cause of this because the radioactive sample and the clocks used to measure the decay rate are in the same reference frame (namely, Earth).

        The simple fact of more curvature can’t even possibly affect decay rates? I don’t know what Eric Albers had in mind, but I’m not thinking frame of reference, just curvature of space – triangles with angles that don’t quite sum to 180 degrees.

        I wouldn’t expect a significant effect because after all the Sun is a fair distance away, so I’d think the effect of variations in the distance from the Sun would be trivial compared with other things. But I don’t really know what the scale of all these things is anyway, and don’t claim to understand general relativity, and certainly can’t do the math.

        But if we ignore the actual scale of the effects and imagine, for example, that our sample was near a black hole – can space-time curvature in itself affect decay rates, independent of frame-of-reference effects? Wouldn’t an extreme curvature mean that the ways that protons and neutrons can be stably packed into a nucleus would be affected?

    • Eric Albers says:

      I don’t mean simple time dialation, radioactive decay rates are a function of spacetime curvature/density. If you want to see large atoms > 120 on the periodic table, bring them into a high curvature space, they will be stable for longer periods.
      Conversely, you can increase decay rates by negatively bending spacetime…at low enough curvature/pressure, the mass will flash to energy as the curvature will not be sufficient to hold the particles or nucleus together.
      Analogy: Bubbles of air as they ascend from the sea grow in size, balloons to the same in air, particles and atoms do the same in curved space.

      • Henning Dekant says:

        I must admit I have never heard of this effect as a prediction from GR. Could you link to some papers?

      • Ross Presser says:

        I doubt the variation in “spacetime curvature” is appreciable between noon and midnight in the same location on the earth, 12 hours apart.

      • John Baez says:

        “I don’t mean simple time dialation, radioactive decay rates are a function of spacetime curvature/density. If you want to see large atoms > 120 on the periodic table, bring them into a high curvature space, they will be stable for longer periods.”

        This is your personal theory, not something most physicists believe.

        • Eric Albers says:

          Ummm, its not my ‘personal theory’, its what I was taught, but whatever, I was merely surprised at the hoopla at the results…please forget I mentioned it…I suppose if you take a buckeysphere of magnet coils with all their poles facing the same direction and apply power you don’t modify the decay rate at the center of the sphere?? Right. Go try it.

          • Henning Dekant says:

            Eric, may I ask who taught you this? I am genuinely curious.

          • Omnicomment says:

            @Eric Albers

            OK, even assuming what you state is an observed phenomenon adopted by mainstream physics, take another look at the data which this post quotes will you?

            The decay rate INCREASES the CLOSER we are to the sun. Which means the decay rate is observed to be larger, when the curvature in space-time is larger.

            So the data mentioned in the post serves as a counter example to your proposed hypothesis, invalidating it…

            …as long as you’re talking about nuclear radioactivity processes involving alpha, beta and gamma decay.

            However, given that we’re probing on smaller and smaller scales, maybe something similar to what you state will be observed with some funky as-yet-undiscovered ‘more-fundamental’ particles; that are on the scales of Planck Length etc. But for now such a modified prediction is “not even wrong”.

  5. Reg says:

    My initial inclination is to an opinion similar to the previous comments.

    However, I’m troubled by the error bars which are of similar magnitude to the periodic measurement variation. This and consideration of the data sample interval and the nature of radioactive decay makes me wonder if the anomaly is not just aliasing as the result of inadequate sampling.

    Averaging by counting events over a regular interval does not eliminate all high frequencies. It applies a sinc(f) filter in the frequency domain to the data. In this case, the spectrum extends to infinity, so aliasing is unavoidable. Preventing it would require resolving individual decay events in time to infinite precision which simply cannot be done.

    Time series analysis is often difficult for the experienced and downright treacherous for the inexperienced.

    • Henning Dekant says:

      Most certainly the associated error with the measurements deserve the highest scrutiny, but on first pass the papers give the impression that the applied methodology is rather thorough.

  6. John Andrews says:

    Since neither experiment has been replicated (or even scrutinized for methodological flaws) I’d call these speculative and tenuous at best.

    • Henning Dekant says:

      Do you mean an exact replication? I.e. religiously following the original set-up? Because to me it seems that the new study replicates the effect from the previous one.

  7. Michael Cecere says:

    I’m a little surprised that the moon is never mentioned at all. It seems like it was even avoided a bit. i suppose some wider reading on my part will address this succinctly since it must be easily addressed.

    • Henning Dekant says:

      In the embedded video somebody asked about the effect of the moon and the presenters asserts that it has been accounted for. (This is very close to the end, during the Q&A session).

  8. Mike Jones says:

    How do these findings affect radiocarbon dating?

    • Henning Dekant says:

      The effect is small and just a modulation on top of the regular decay curve, so for carbon dating this should pretty much average out.

      But if neutrinos can modulate the decay rate it’ll mean that other astronomical events such as close by super novae explosions may shift the signal to some extend.

      • Darren Addy says:

        I’m no expert, but apparently a link between supernova and carbon-14 is already understood. http://www.metafilter.com/119540/Cosmic-Ray-mystery

        • Henning Dekant says:

          Spikes in cosmic radiation from a supernova are understood to produce more Carbon-14 (the latter comes from the atmospheric nitrogen transmuted by cosmic radiation that usually can be assumed as a constant background).

        • Jeff Berkowitz says:

          I’m no expert either, but I can read a Wikipedia page: http://en.wikipedia.org/wiki/Radiocarbon_dating
          Essentially *all* the 14C is created as a result of cosmic ray interactions. I can’t for the life of me see what this has to do with the topic at hand, though.

          • Omnicomment says:

            Did you not read the Wikipedia page thoroughly enough? So far, science thinks decay rates are ‘constants’.

            Those ‘constants’ appear in the formula used to calculate a date, via Carbon Dating. If the ‘constants’ are no longer constant – it changes how old things are ‘measured’ to be.

  9. Daniel Pfenniger says:

    For an astrophysicist like me, the assumption that element decay is independent of the environement is obviously an approximation which is not true in all circumstances. A simple example that comes to mind is the neutron life time, about 10 min, which becomes infinite in very dense conditions like in neutron stars.

    Conversely in very hot conditions radioactive lifetimes are shortened by mere nuclei collisions.

    • Henning Dekant says:

      Certainly food for thought. Once gravity potential differential on the atomic scale reach the level of the Fermi energy things are certainly not that clear cut anymore.

  10. Navneeth says:

    Do you have a link to the video?

  11. mmu_man says:

    Please, please, please, stop using on the SWF when including youtube videos. This fails to deliver the HTML5 player when possible. Flash is not an open format, is not a W3C standard, and so is not part of the Web and should just disapear as prehistoric artefact of the Net. It does not work in GNU/Linux without installing proprietary software or an unfinished clone, it does not work either in Haiku, nor in many other OSes, nor on the iThings, and poses many accessibility issues.

    The correct (and advertised by youtube) way is to use an IFRAME tag on http://www.youtube.com/embed/3RWX9XGCdm0

    I invite others to activate the HTML5 player as well to show support:
    http://www.youtube.com/html5
    (sadly not all videos are available as such, but it’s a start, at least it avoids having to youtube-dl/clive/cclive/videoob them)

    Thanks for not hurting the Web.

  12. Jonathan Hunsberger says:

    Is it possible that only the *measurement* of the decay rates is affected by the solar radiation?

    • Henning Dekant says:

      Absolutely. At this point this is just some really odd observation and they make a pretty good case of the sun’s influence, but this needs to be scrutinized from all angles.

  13. Konstantin says:

    One explanation for these patterns could be cosmic background radiation that has similar yearly patterns. This radiation can contribute to the signal as systematic background that is difficult to factor out.
    Radioactive decays are measured by the same instruments that are used in particle and nuclear physics – particle physics has it’s beginning in measuring cosmic radiation and atmospheric showers.

    • Henning Dekant says:

      Good point, but the seasonality in the background doesn’t really match the claimed pattern very well.

      • Tony J Carey says:

        As far as I am aware it is still not possible to say whether the annual cycles correspond with the Max/min Earth-Sun distance or the Max/min absolute velocity with respect to the cosmic microwave background – ie to distinguish
        between a peak at a minimum solar distance on Jan 4 or at the max cosmic velocity close to Dec 21.

  14. mmu_man says:

    Oddly, my Firefox doesn’t show the Cs_normal_decay-1024×706.png picture, it complains it “contains errors”, while downloading and opening it with various software works… odder is it displays the local copy with file: just fine. :^)

    • mmu_man says:

      Nevermind, Firefox needed a restart I guess.

      • Henning Dekant says:

        Glad to hear that’s all there was to it. I rely on a WordPress plug-in for embedding youtube videos and only cursory tested it on my iPad to see if it works without Flash.

  15. AK says:

    I think your presentation of this is a little one-sided. I’m not an expert on this subject, but it’s not like these are the only two papers in the field. The experimental situation is much more complicated. For instance, take a look at “Evidence against correlations between nuclear decay rates and Earth-Sun distance,” http://arxiv.org/abs/0810.3265, which finds no correlation, or an analysis of data from spacecraft, “Searching for modifications to the exponential radioactive decay law with the Cassini spacecraft,” which as pointed out by Dennis, should be more sensitive to this sort of thing: http://arxiv.org/abs/0809.4248.

    Neither of these papers finds evidence of the correlations proposed by Jenkins et al. In addition, note that the most recent paper (Sturrock et al.) is not actually an independent confirmation – Jenkins is the last author on that paper.

    Maybe this will turn out to be accurate (I hope so – it would be cool!), but it looks like the solar correlation is only being found by one group of scientists, which should engender a little more skepticism.

    • Henning Dekant says:

      Some very good counter arguments have been put forwarded in the associated /. thread.

      When I find some time over this long weekend I will compile them in an update to this post to give a somewhat more balanced picture.

  16. justin says:

    The phase shift noted in the paper is interesting to me.

    I’m just a layman, but my first impression is that such a phase shift would be natural if these neutrinos or unknown rays from the sun were capable of knocking nuclei of a particular isotope into a slightly different configuration (or metastable state) from which they would then decay (via α or β emission) with a much shorter half-life, (perhaps on the order of month or so, looking at the chart for Si-32.)

  17. Josh says:

    Can we correlate the decay rate deviations with ambient temperature?
    Can we try heating up the source material and the measurement equipment at night in winter?

    • Henning Dekant says:

      One would hope that seasoned experimentalists know how to account for these kind of environmental effects, but these are certainly valid questions.

    • Ricardo K Almeida says:

      If there were a temperature dependence on decay rate, this would have been found out many decades ago. Otherwise I’ll stop trusting any experimental results in physics.

      • Henning Dekant says:

        Ricardo, you are of course entirely correct. I should have been more clear: Any impact of temperature in the data would be due to the measuring devices. I.e. the sensitivities of a Geiger counter can vary with the temperature.

  18. Eric Albers says:

    Ummm, its not my ‘personal theory’, its what I was taught, but whatever, I was merely surprised at the hoopla at the results…please forget I mentioned it…I suppose if you take a buckeysphere of magnet coils with all their poles facing the same direction and apply power and a charge potential to the sphere you don’t modify the decay rate at the center of the sphere??
    Ya, Right. Go try it. Whats news, this is not news basic physics first year stuff

    • Eric Albers says:

      I cannot believe the number of weird messages I get on this,

      come on, this is stuff we played with at 13,

      Take 2d magnets, where d is dimensions, or 6,

      Place the 6 electromagnets so that the come together at a central point,

      Power them up so all North poles are at the center,

      Apply a charge C to the crude ‘sphere’ of only 6 polygons,
      Place Amercium at the center, place same amount outside as control
      Meausre Gamma only from one in sphere, and gamma only from out outside

      Vary I (amps) and C (columbs) to sphere and watch decay rate change.

      Duh, its a great science faire exhibit, but really, the sun distance vs decay rate is well known effect guys.

      • Ian says:

        You’ve tried this yourself, right? How do you know the electric and magnetic fields aren’t interfering with your instruments?

      • Henning Dekant says:

        Amercium is an alpha emitter. An electromagnetic field will influence the charged alpha particles trajectory and hence influence the flux towards the Geiger counter. It will not influence the decay rate itself.

        The sun distance claim is highly controversial.

        Are you sure you are not a visitor from some parallel universe, or are you just having some fun at our expense?

  19. John Taylor says:

    The change in the decay rate is interesting but not as yet associated with it’s cause.

    1) It could be gravitational/space time curvature related … If so we should see a modulating component relating to the position of the moon.

    2) It could be solar particle/radiation related … if so, we should see an interference during transits of the Moon Venus, and Mercury only.

    3) It could be due to some as yet unknown situation that our physics has not yet discovered. We have Dark matter & dark energy, why would we be overly surprised to discover a dark force, a dark field, or a dark dimension.

    One thing we do know is that we are in no danger of running out of new things to study in Physics.

    • Maury Markowitz says:

      Nice summation John. Of course, #3 piques the interest the most :-)

      I don’t really understand the intricacies of the Standard Model very well, but from the little I do understand there would seem to be a potential channel through the weak force for this sort of reaction. In fact, I’m surprised such a reaction is not part of the basic corpus of physics, which leads me to believe I don’t understand the weak interactions very well.

    • Henning Dekant says:

      In the video somebody asked about moon periodicities, they apparently checked for this but came up empty.

      • John Taylor says:

        The moon modulation has not shown up but with the random component of decay involved we may simply need to build up more data points to see if the modulation shows at a greater level of precision. Still, it is a very good indication that the effect is not associated with gravitational/space time curvature.

        Now to have someone look back in the data to the time period when we had the transit of Venus and see if we can spot some specific interference during that brief time, and confirm a similar interference during moon eclipses or mercury transits.

  20. 123star says:

    Hi Henning,
    Thank you for providing these info to us!
    Let’s assume that this phenomenon is real. If the sun distance claim is to be dismissed, the only other parameter that comes to my mind that could explain the annual variation could be the sun’s axis tilt (which is about 7°). The additional assumption is that the sun neutrino’s flavour composition angular distribution is anisotropic (along the lines of longitude). Note, here I am assuming that the rotation north of the sun coincides with his magnetic north.
    Is this what the authors of the article “Analysis of Gamma Radiation from a Radon Source: Indications of a Solar Influence” suggest in the conclusion?

    Also I would say a word about neutrinos, assuming they are responsible of the phenomenon. If the decay rate changes with the hour of the day, that would mean that the passage of neutrinos through earth radically changes things. Now is the MSW effect through earth enough to explain this daily oscillation (because it would change neutrino’s flavor composition)? I doubt it, but I didn’t make any calculation, so I’m not sure. At this point then, hypothesizing a “mystery particle” which is easily shielded by earth (unlike neutrinos) could be more plausible, but it’s a long shot. Let me know what you think,

    123star

    • Henning Dekant says:

      Impressive. I assume you wrote this without watching the video? Because the sun’s axis tilt is explicitly mentioned there.

      I am with you on the earth shielding, it shouldn’t be that noticeable unless there’s something else at play.

  21. Piti says:

    I’m going to ask the obvious. Are you sure this is not something as simple as cosmic ray count fluctuation in geiger counter/photo tube etc.? I couldn’t find much on the experiment setup and background reduction. I mean when it’s noon less earth stuff is between sun and your experiment thus it’s easier for whatever that comes from the sun and interacts with atmosphere to get to your detector.

    It’s easier to test this hypothesis: just run your experiment without source: just cosmic ray and see if you still see the same effect or use different source that give out at least 2 charge particles so you can trigger very cleanly.

    • Henning Dekant says:

      My blog post is based on the information available in the papers and the video. Ultimately, I place some trust into the authors. One would hope that seasoned experimentalists from renowned physics depts to not make such obvious mistakes.

      • Elijah Gregory says:

        I agree, one would hope physicists would account for these fluctuations, and indeed, it is very simple to maintain a room at a constant temperature throughout the day. Not to mention some data was obtained deep underground, where temperature fluctuations from the sun are negligible or non-existent. I was thinking experimental error, but on second thought it seems unlikely.

        One issue is they are trying to tease out a cause and effect from a correlation in their data, so *how* they average things is going to effect the degree to which they see the effect. To get around this, pay the most attention to the center of their data, free from edge-effects, and we definitely do see the correlation is spot-on there.

        One reason this hasn’t been noticed before is a sense that we *are* hand-picking data when we simply look for cycles with periods that match up with the data. They have graphs with data spanning years, if they measured and plotted a data point every minute of those years, would the effect be more or less obvious?

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  25. Daniel Pfenniger says:

    A undiscussed source of neutrinos with possible annual modulation is the Cosmic Neutrino Background, which is the analogue of the Cosmic Microwave Background for photons, but was created 1s after the Big Bang instead of 350’000 yr. These very low energy neutrinos (10^-4 eV) predicted by the Big Bang scenario must fill now the universe with a higher density (~330/cm^3) than the Sun neutrino density ( 3/cm^3). The Earth moves relative to this neutrino background with a speed changing by about +- 30 km/s over a year, with a maximum/minimum for the months of June/December respectively.

    From the Fig of Gamma measurements the maximum/minimum occur slightly *before* the mid-year (June) of end of year (December) so the link with the neutrino background provides a better phase match than the Sun-Earth distance correlation which has a maximum/minimum in January/July.

    • Henning Dekant says:

      Very interesting observation. Especially since this background flux is supposed to be higher than what comes from the sun.

      Haven’t seen this raised anywhere in connection to this (still highly contentious) issue.

      If this was the source for an actual super-imposed variation in the decay rate, a simple space probe based test for a sun-earth distance relationship will not do.

    • 123star says:

      I’d like to point out that this would not explain the variation of the decay rate with the time of the day: in the cited article the decay rate is maximum at noon, so the reference is the sun and not an absolute direction.
      By the way, I am more and more inclined to suspect that the variation of the decay rate is just an artifact due to the variation of the temperature of the measuring apparatus, which is not thermostated.

      • Henning Dekant says:

        To the extend that the decay rates were measured in an indoor lab one wouldn’t expect temperature to factor in.

    • Tony J Carey says:

      See my earlier post:
      “As far as I am aware it is still not possible to say whether the annual cycles correspond with the Max/min Earth-Sun distance or the Max/min absolute velocity with respect to the cosmic microwave background – ie to distinguish
      between a peak at a minimum solar distance on Jan 4 or at the max cosmic velocity close to Dec 21.”

      • Henning Dekant says:

        Tony, my understanding is that you are right about this. Should be within the standard error width given how faint the pattern is.

  26. Matthew W.S. Bell says:

    On the 2D plot of gamma, is it just me, or are there smaller peaks between the larger ones that correspond with the solar elevation plot.

  27. Mark says:

    This reminds me of a paper I read a while ago by Gustav Le Bon. He states exactly this, and it was written around the end of the 20th century.

    The evolution of matter I think it was called.

    He also states that non radioactive elements can be rendered active by the influence of the sun. Claims that copper roofing is radioactive for example.

    Keep up the good work science chaps!

  28. Nikolay Pavlov says:

    Obviously, in such long time mesaurements, there is high risk of observing artefacts caused by e.g. temperature or air pressure impact on the efficincy of the detector.
    Cosmic rays also may cause such changes by inducing some invisible dead time in the detectors.
    I think the experiment should be performed using e.g. two gamma emitters like Co-60, Na-22 and coincedence/non-coincednce counting with two counters.
    Observation of ratio of coince /non-coinc rate will allow to maintain precise calibration of the counter’s efficiency.

    • Henning Dekant says:

      One conjecture is that this effect is due to neutrino weak force interaction that’ll limit it to beta decay channels. If that’s the case then nothing should show up with gamma emitters.

      I certainly hope that there will be follow up measurements across a wide variety of isotopes. They will take a pretty long time to be conclusive but should be relatively inexpensive.

  29. Hehasnoname says:

    And thus carbon dating has now been ruled moot… =P

    Time to rewrite physics…

    • Henning Dekant says:

      You need to read the article more carefully and look at the charts in some more detail. The effect, if real, is very small, and will only introduce a minute error. Since this is only a small annual variation, over a long time scale, the half life will average out.

      • CuriousChris says:

        My brother a devout Christian and Creationist heard about this anomaly very soon after it was announced and promptly sent me details. He of course believed it was vindication for his belief in a young world.
        I replied advising him of the actual error percent it introduces and finished up with the quote…

        “Dinosaurs first arose around 230 Million years ago, I really don’t care that it was a Wednesday”.

        He good humouredly conceded defeat. But nevertheless clings to his superstition.

        Keep up the good work Q :)

  30. Mark Vervest says:

    My initial believe was that this effect should have been measured in the lifetime of free neutrons and therefore could not be real. My gut reaction was that it should have been detected decades ago in at least ‘some’ particle physics experiments.

    But when I tried to find out what the lifetime of a free neutron was, I found out that we still lack clarity and accuracy in the data and of the experimental setups. The reasons for this is that the experimentation is still extremely difficult for an uncharged particle, allowing systematic risks to creep into the analysis unnoticed.

    The error bars have steadily reduced over the years to second/sub-second values. But there still is an issue with the measured values of the lifetime between the individual experiments:
    The Particle Data Group, an international collaboration that acts as an authority on subatomic particle properties, currently puts the neutron lifetime at 881.5 seconds (14 minutes, 41.5 seconds). This number is an average of the best seven measurements in the last two decades, weighted based on precision. But the values included range from 878.5 to 889.2 seconds. To say something new and interesting about physics, scientists need consistent independent experiments that pin down the neutron lifetime to within a second.
    Source

    Although this does not prove the effect is real, it certainly is interesting in this context. Of course, the most believable cause for this problem are systematic errors in the experiments. But perhaps it is worth a shot to ask at what time of the year these measurements were taken and see if the pattern is similar to the observed effect.

  31. “From the Annals of the Impossible (Experimental Physics) | Wavewatching” in fact makes me think
    a tiny bit extra. I really admired each and every individual part of it.
    Regards -Catherine

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  33. in this website is an explonation for the found phanomena, how neutrinos tgigger the radioactive decay.