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dgruss23
2008-Aug-27, 03:37 AM
Jenkins et al (http://xxx.lanl.gov/abs/0808.3283) find evidence that the rate of nuclear decay of Si-32 and Ra-226 has an annual variation that correlates with the Earth-Sun distance. They are not sure what the mechanism is for this correlation. One possibility they discuss involves the fine structure constant while the other is tied in with solar neutrinos.

dgruss23
2008-Aug-27, 03:45 AM
If Neutrino's are involved in the explanation for this phenomenon it will be interesting to see if that mechanism then would have an impact on studies of supernova - such as this one (http://xxx.lanl.gov/abs/astro-ph/9712223) - that take a look at decay rates of radioactive isotopes.

Jenkins (http://xxx.lanl.gov/abs/0808.3156) also presented this related result.

Kaptain K
2008-Aug-27, 03:46 AM
Yee-haw! That certainly puts a crimp in the long held idea that radioactive decay is immutably constant!

Jerry
2008-Aug-27, 04:02 AM
Ah some! I looked for this in the decay parameters of both the Pioneer probes and the Voyager data. Voyager has been kicking out more watts than expected, but it is assumed to be more efficient functioning of the thermalcouples.

The implications go well beyond fine constants - suddenly there is no meaningful agreement between time dilation and mass - The Einstein equivalence principle flys right out the window. What happens to the decay rate, and energy, in extremely dense environments? This looks to have the potential to be a breakthrough observation, Degruss - nice find.

borman
2008-Aug-27, 04:49 AM
I notice that they say it could be related to the DAMA/LIBRA signal. But we are no closer to sorting out whether it is due velocity against some WIMP wind or whether it is due to Delta V from approaching and leaving the sun as the Earth moves in its eccentric orbit. If a spacecraft were placed in a circular orbit around the sun and the signal was still there,thus cancelling any Delta V due to eccentricity, this would rule out the Delta V idea and support the simple velocity idea put forth by the DAMA/LIBRA collaboration. Otherwise it may be an e(sinE) correction or a post relativistic correction to e(sinE).

timb
2008-Aug-27, 07:50 AM
Has this stuff ever passed peer review?

tusenfem
2008-Aug-27, 07:59 AM
And why cannot it be annual variations in the measuring equipment?

dgruss23
2008-Aug-27, 11:21 AM
And why cannot it be annual variations in the measuring equipment?

The authors pointed out that you have two independent data sets (one for Si-32 and one for Ra-226 which were carried out at two different locations on Earth with different climates. There are two years of overlap in the data which show similar fluctuations.

dgruss23
2008-Aug-27, 11:43 AM
Has this stuff ever passed peer review?

It doesn't say what the publication status is, so it is possible it is under review. Authors posting on arXiv sometimes post their papers before review is completed because some journals take a very long time to review a paper.

An earlier (http://adsabs.harvard.edu/abs/1986E%26PSL..78..168A) study also found evidence for a seasonal variation in the decay rate of Si-32. So this paper's results are not without a prior basis.

tusenfem
2008-Aug-27, 12:49 PM
The authors pointed out that you have two independent data sets (one for Si-32 and one for Ra-226 which were carried out at two different locations on Earth with different climates. There are two years of overlap in the data which show similar fluctuations.

Okay, I guessed I missed that in quickly looking at the paper.

trinitree88
2008-Aug-27, 06:09 PM
Jenkins et al (http://xxx.lanl.gov/abs/0808.3283) find evidence that the rate of nuclear decay of Si-32 and Ra-226 has an annual variation that correlates with the Earth-Sun distance. They are not sure what the mechanism is for this correlation. One possibility they discuss involves the fine structure constant while the other is tied in with solar neutrinos.

dgruss. Radioactive decays occur at different rates within the floors of a high rise office building from GR considerations....and there is a differential neutrino flux between them.
They also have extended half-lives due to SR...muons in accelerator labs...that experience a different neutrino flux than their sitting counterparts.
Solar proximity changes both GR considerations..(sun's well)...and SR considerations...Keplerian velocity increase....as well as the ambient neutrino fluxes.
Not a surprise. pete

Free neutrons have a dramatic change in radioactive decay rates as ambient magnetic fields approach 1011 to 1013 Gauss...on the order of strength of many pulsars.

see:
http://www.nature.com/nature/journal/v222/n5194/abs/222649b0.html

ans see:
http://www.bautforum.com/questions-answers/32894-question-about-neutron-stars.html

or:http://www.bautforum.com/questions-answers/51460-neutrons-unstable-how-come-neutron-stars-stable.html

dgruss23
2008-Aug-27, 06:35 PM
dgruss. Radioactive decays occur at different rates within the floors of a high rise office building from GR considerations....and there is a differential neutrino flux between them.
They also have extended half-lives due to SR...muons in accelerator labs...that experience a different neutrino flux than their sitting counterparts.
Solar proximity changes both GR considerations..(sun's well)...and SR considerations...Keplerian velocity increase....as well as the ambient neutrino fluxes.
Not a surprise. pete

Free neutrons have a dramatic change in radioactive decay rates as ambient magnetic fields approach 1011 to 1013 Gauss...on the order of strength of many pulsars.

see:
http://www.nature.com/nature/journal/v222/n5194/abs/222649b0.html

ans see:
http://www.bautforum.com/questions-answers/32894-question-about-neutron-stars.html

or:http://www.bautforum.com/questions-answers/51460-neutrons-unstable-how-come-neutron-stars-stable.html

This is interesting, but very new to me. Textbook treatment of radioactive decay always emphasizes that the half-life of a radioactive isotope is a constant - hence useful as a method of dating ages. Are you saying this is a simplification for pedagogical purposes?

Also, the sources you note involve neutron decay. How is this related then to radioactive decay of a nucleus (alpha and beta decays)? I'm trying to understand how far one must travel up the ladder of expertise in nuclear physics before fluctuation of radioactive decay half-life rates becomes a "well of course that is the case" understanding. You never see this discussed in popular literature or introductory textbooks in physics and chemistry. I'd suspect this result would be quite surpising to most people outside the research specialists.

antoniseb
2008-Aug-27, 06:39 PM
If these studies hold up, I'd be interested in seeing some similar tests done deep underground, fair from the influence of neutral muons.

trinitree88
2008-Aug-27, 08:23 PM
If these studies hold up, I'd be interested in seeing some similar tests done deep underground, fair from the influence of neutral muons.

antoniseb. It must vary there,too. If the strength of the gravitational field changes, then the ticking of the "clock" that is the radionuclide, or unstable particle in the Standard Model also changes....hence, new half-life. It's small, but perceptible with good experimental technique.
A point of order. There are no neutral muons. Muons come in two types...u+ and u-. The u+ decays to a positron,(e+), an electron type neutrino (ve), and a muon-type antineutrino (vu)-

The u- decays into an electron, e-, an electron-type antineutrino, and a muon-type neutrino. see: WIKI link.
http://en.wikipedia.org/wiki/Muon#Muon_decays

While the underground chamber will dodge a lot of the ambient cosmic ray flux, and it's secondary muonic flux, whatever you do to change the shielding further, increases the neutrino gradient changes. pete

antoniseb
2008-Aug-27, 08:38 PM
...If the strength of the gravitational field changes, then the ticking of the "clock" that is the radionuclide, or unstable particle in the Standard Model also changes....

The scale of differences seen in this study are far outside the range of relativity's influence.


A point of order. There are no neutral muons. Muons come in two types...u+ and u-. The u+ decays to a positron,(e+), an electron type neutrino (ve), and a muon-type antineutrino (vu)-


You're right. I was thinking neutral pions, but was posting ad hoc with a need to get off-line fast, and made an error.

trinitree88
2008-Aug-27, 08:45 PM
This is interesting, but very new to me. Textbook treatment of radioactive decay always emphasizes that the half-life of a radioactive isotope is a constant - hence useful as a method of dating ages. Are you saying this is a simplification for pedagogical purposes?

Also, the sources you note involve neutron decay. How is this related then to radioactive decay of a nucleus (alpha and beta decays)? I'm trying to understand how far one must travel up the ladder of expertise in nuclear physics before fluctuation of radioactive decay half-life rates becomes a "well of course that is the case" understanding. You never see this discussed in popular literature or introductory textbooks in physics and chemistry. I'd suspect this result would be quite surpising to most people outside the research specialists.

dgruss. Yes. I was quite surprised as a young teacher, to find that half-lives were metastable to some degree. Under most reasonable expectations for varying field strengths in the geologic history of the Earth, and the solar system, it is trivial, and assumed constant, which is why many texts do not treat it.
In an astrophysical sense, nuclear physics sense, and particle physics sense, one is more likely to encounter fields not seen in the lab, and theoretical sections might treat it. A Prof. friend at MIT quite matter of factly addressed it in conversation, after I brought it up, having found a reference in a Soviet Journal of Nuclear Physics article. I was equally surprised then. Off the top of his head he quoted the range of field strength that involved what is known as the "shoulder" of the half-life. If you plot half-life on the y axis, and gradually increase the field an order of magnitude across x...it reaches a point where the curve plummets...hence, "the shoulder" of the curve.
Neutron decay is a beta decay. The high speed electron is generally produced...(although it can sometimes be fairly slow), and an electron type antineutrino is also produced by the free, (or bound) neutron. If the electron is fast, the antineutrino is not energetic. If the electron is slow, the antineutrino is energetic. The total energy of the disintegration is constant, and teasing out the involvement of the antineutrino in the decay took years of experiment and theory. ...Pauli,Fermi, Cowan, Rheines,etc. pete

Ara Pacis
2008-Aug-28, 03:00 AM
Okay, so does this mean we get FTL spaceships or not? :-/

Kaptain K
2008-Aug-28, 03:58 AM
I wish!

George
2008-Aug-28, 04:04 AM
Are there any blips during a solar eclipse?

Jens
2008-Aug-28, 04:12 AM
Are there any blips during a solar eclipse?

Interesting question. Apparently an experiment was just conducted on that. See here (http://www.afrc.af.mil/newsreleases/story.asp?id=123108330).

parejkoj
2008-Aug-28, 05:37 AM
Also, the sources you note involve neutron decay. How is this related then to radioactive decay of a nucleus (alpha and beta decays)? I'm trying to understand how far one must travel up the ladder of expertise in nuclear physics before fluctuation of radioactive decay half-life rates becomes a "well of course that is the case" understanding. You never see this discussed in popular literature or introductory textbooks in physics and chemistry.

Personally I hadn't thought much about it, but I would be surprised if weak-interaction decays (such as nuclear beta decay) did not vary with varying neutrino flux. Pair-production (e-/e+) by gamma-rays with E>1.022MeV needs a mediator (typically an atomic nucleus) to carry off some of the gamma's momentum; if the number of potential mediators changes, the pair-production rate will change, assuming constant gamma flux and energy. Similarly, if the neutrino flux changes, I would expect a different decay cross-section because of the change in the number of leptons floating around.

I'll try and check some nuclear physics books when I get back to my office (Friday, or next week), and see whether they describe such cross-sections.

I haven't had time to look at these papers yet, and I can't say anything about what the order of magnitude of the effect should be. Except to say that "radioactive decay rates are constant" is an excellent approximation in most cases.

George
2008-Aug-28, 12:28 PM
Interesting question. Apparently an experiment was just conducted on that. See here (http://www.afrc.af.mil/newsreleases/story.asp?id=123108330). :cool:


Personally I hadn't thought much about it, but I would be surprised if weak-interaction decays (such as nuclear beta decay) did not vary with varying neutrino flux. Pair-production (e-/e+) by gamma-rays with E>1.022MeV needs a mediator (typically an atomic nucleus) to carry off some of the gamma's momentum; if the number of potential mediators changes, the pair-production rate will change, assuming constant gamma flux and energy. Similarly, if the neutrino flux changes, I would expect a different decay cross-section because of the change in the number of leptons floating around. I thought this had been well tested in light of YEC claims. Perhaps great accuracy was not used, as it would not be needed in this case.

trinitree88
2008-Aug-28, 06:23 PM
[QUOTE=parejkoj;1310171]Personally I hadn't thought much about it, but I would be surprised if weak-interaction decays (such as nuclear beta decay) did not vary with varying neutrino flux. Pair-production (e-/e+) by gamma-rays with E>1.022MeV needs a mediator (typically an atomic nucleus) to carry off some of the gamma's momentum; if the number of potential mediators changes, the pair-production rate will change, assuming constant gamma flux and energy. Similarly, if the neutrino flux changes, I would expect a different decay cross-section because of the change in the number of leptons floating around.SNIPPET


parejkoj. I thought about this a long time ago, and concluded that if the neutrino flux changes, everything changes....rates of ticking clocks, lengths of meter sticks, masses of particles, and geometric rotation of passing bodies. There are two indirect ways of changing the neutrino flux...bring in a massive body to intercept some of it, or accelerate through it, and one direct way...use a neutrino beam or spallation source (reactor,or bomb, or supernova).
The first two are intimately tied to GR and SR...the third is a little trickier. I'm betting Mossbauer detectors "saw" SN1987a, but that data is likely classified. pete

parejkoj
2008-Aug-28, 06:34 PM
Now that I've looked at the paper in the OP, they note a fractional change in the counting rates of ~3e-3, which is a good bit larger than I would have expected (given that I had no real idea what the order of magnitude would be). But that is certainly small enough that it doesn't matter when discussing things like radiocarbon(argon,etc.) dating, where the errors are more like 5%.

They mention that a similar type of decay experiment placed near a nuclear reactor could be used to test the neutrino-mediator hypothesis. I know some people who are working on a next-gen reactor neutrino experiment. I'll ask them if any such plans are underfoot.

parejkoj
2008-Aug-28, 07:01 PM
parejkoj. I thought about this a long time ago, and concluded that if the neutrino flux changes, everything changes....rates of ticking clocks, lengths of meter sticks, masses of particles, and geometric rotation of passing bodies. There are two indirect ways of changing the neutrino flux...bring in a massive body to intercept some of it, or accelerate through it, and one direct way...use a neutrino beam or spallation source (reactor,or bomb, or supernova).


Or just move farther from the flux source, since the number of neutrinos crossing a given area falls off as 1/r2. I don't see why this would change the other things that you mention (clocks, lengths, masses, etc), since neutrinos only interact via the weak force. The solar neutrino flux would also change if the rate of fusion in the sun's core changes.

Incidentally, on some more thought, this result probably has zero effect on current determinations of decay rates relevant to radioactive dating, since those would be empirically determined from long time-series data. Thus, any annually-varying effect like this would get "averaged out." Assuming it is due to solar effects and not something else...

borman
2008-Aug-28, 10:22 PM
I wonder if neutrino oscillation might figure into this with the solar flare connection. Could a Tau neutrino bath make for a change in decay rate compared to an electron neutrino bath? The Fermi lab was doing experiments to verify neutrino oscillation until funds were threatened. Monitoring the same samples at different places along the oscillation path might show if oscillation is involved.

William
2008-Aug-29, 02:02 AM
I thought the authors stated in their paper that the observation could not be explained using neutrinos (I am assuming there is a fundamental difference between alpha and beta decay, one is associated with the strong force and the later with the weak force. Are neutrinos only associated with the weak force?). The authors state in their paper that the explanation for the phenomenon must be some scalar field and then provide a link to two papers by Shaw.

The following is a link to the two papers that authors of the original paper referenced.

The following two paper are not connected.

One paper proposes that gravitation field variance affects fundamental constants. I do not see how variations in the total gravitational field due to changes in the sun-earth distant could explain the observation as it is far too small as compared to the earth's gravitational field. (i.e. If the very small solar gravitational field strength variance cause this effect in a strong field the effect would be orders of magnitude greater.)

The other paper notes constants are not constant and could change with time.

Note everyone (authors and comments in this thread) are ignoring that there is a clear observed phase lag for the effect. The effect lags the change in the sun-earth distance. As gravitational changes are per the GR theory at the speed of light and neutrinos also travel at near light speed, those mechanisms cannot explain a time lag in the effect. Probably the time lag would in fact rule both of those mechanism out (In addition to the reasons noted above and below.)

Note the interesting finding, in the paper that asserts that the fundamental constants change with time. That paper asserts there is data that shows the electron/proton ratio varies with redshift.


Detecting Seasonal Changes in the Fundamental Constants


We show that if one or more of the `constants' of Nature can vary then their values, as measured in the laboratory, should oscillate over the year in a very particular way. These seasonal changes in the constants could well be detected, in the near future, with ground-based atomic clocks.


http://arxiv.org/abs/gr-qc/0702090v1


Varying Alpha: New Constraints from Seasonal Variations

http://arxiv.org/abs/0806.4317v1


We analyze the constraints obtained from new atomic clock data on the possible time variation of the fine structure `constant' and the electron-proton mass ratio and show how they are strengthened when the seasonal variation of Sun's gravitational field at the Earth's surface is taken into account. We compare these bounds with those obtainable from tests of the Weak Equivalence Principle and high-redshift observations of quasar absorption spectra consistent with time variations in the fine structure constant.


Comment:
I suppose this phenomena would affect other radioactive isotopes and elements. Would the affect be the same for all radioactive isotopes/elements?

I am thinking about an alternative strawman mechanism (Definitely needs more work, however, before facing ATM.) which if correct would predict a change in the radioactive decay rate in response to the recent change in the sun. Come to think about it that mechanism would also explain the observed time lag in the effect and the variance of the electron/proton ratio with redshift.

I would also be interested to see if the number of neutrinos emitted by the sun changes.

George
2008-Aug-29, 03:55 PM
Perhaps some of the other things happening during this Solar minimum are contributing, as is being reported in this thread (http://www.bautforum.com/astronomy/68781-solar-cycle-24-a.html). The Solar Constant has now dropped by 2 w/m^2, and magnetic strengths seem much lower than expected.

Perhaps it's not the distance to the Sun that is key, but rather our relative orbital position with the Sun and its protective magnetic protection from the background particle flux. [An amateur's armchair speculation, of course.]

parejkoj
2008-Aug-29, 08:22 PM
Well, I just talked with one of our resident neutrino experts about this. His opinion is that they probably just don't fully understand their background. There are roughly a zillion things that vary on annual timescales (apparently some particle experiments can tell you how much snowfall there was on-top of nearby mountains!), so until they've really hammered on understanding the background, "I wouldn't put much stock in this."

Remember, there isn't really a detector for a specific type of particle or decay, but rather a geiger counter with different window thickenesses and different energy and timing thresholds. So unless the background is very well characterized, you can't distinguish individual decay events from individual background events. And things like the low-energy cosmic ray flux do vary with the Earth's atmospheric height--and thus annually.

Also, my previous thought that the neutrino flux should matter is rather incorrect (to say the least), except for outrageously large neutrino fluxes (such as are produced in a supernova), and then its a different effect from what I was thinking. The neutrino flux from the sun is ~109 / cm2, while the interaction cross-section is ~10-44 / cm2. Oops... guess I got that one wrong! But, if there is a very large neutrino flux, you can change the relative likelihood of different reactions, which can change the "decay rate," but the actual decay processes will be different. But that should not have any effect at these scales.

George
2008-Aug-29, 08:42 PM
Also, my previous thought that the neutrino flux should matter is rather incorrect (to say the least), except for outrageously large neutrino fluxes (such as are produced in a supernova), and then its a different effect from what I was thinking. The neutrino flux from the sun is ~109 / cm2, while the interaction cross-section is ~10-44 / cm2. Oops... guess I got that one wrong! But, if there is a very large neutrino flux, you can change the relative likelihood of different reactions, which can change the "decay rate," but the actual decay processes will be different. But that should not have any effect at these scales. I too assumed neutrino flux might make a difference because of their interaction with the weak force, but I then learned studies had already been done that showed decay rates are not affected by neutrinos (ignoring extreme circumstances). This was several decades back, I think.

VanderL
2008-Aug-30, 10:29 AM
Well, I just talked with one of our resident neutrino experts about this. His opinion is that they probably just don't fully understand their background. There are roughly a zillion things that vary on annual timescales (apparently some particle experiments can tell you how much snowfall there was on-top of nearby mountains!), so until they've really hammered on understanding the background, "I wouldn't put much stock in this."

Remember, there isn't really a detector for a specific type of particle or decay, but rather a geiger counter with different window thickenesses and different energy and timing thresholds. So unless the background is very well characterized, you can't distinguish individual decay events from individual background events. And things like the low-energy cosmic ray flux do vary with the Earth's atmospheric height--and thus annually.

I would think that background signals are very easy to correct for, by directly measuring those counts. I haven't read the paper, but I can't believe an explanation that simple would not have been addressed by the authors. I'll check later this weekend.

Cheers.

hhEb09'1
2008-Aug-30, 11:28 AM
Note everyone (authors and comments in this thread) are ignoring that there is a clear observed phase lag for the effect. The effect lags the change in the sun-earth distance. As gravitational changes are per the GR theory at the speed of light and neutrinos also travel at near light speed, those mechanisms cannot explain a time lag in the effect. Probably the time lag would in fact rule both of those mechanism out (In addition to the reasons noted above and below.)I take it you've just eyeballed their charts, and see a phase lag? There does seem to be a small lag.

The galactic center is very close to the axis of the earth's orbit, but in time progression, it's in the opposite direction from the lag!


I would think that background signals are very easy to correct for, by directly measuring those counts. I haven't read the paper, but I can't believe an explanation that simple would not have been addressed by the authors. I'll check later this weekend.There seem to be some very old dates in there (early 80's). Has the data been analyzed before then?

William
2008-Aug-30, 02:28 PM
In reply to hhEb09'1's comment:


Quote:
Originally Posted by William View Post
Note everyone (authors and comments in this thread) are ignoring that there is a clear observed phase lag for the effect. The effect lags the change in the sun-earth distance. As gravitational changes are per the GR theory at the speed of light and neutrinos also travel at near light speed, those mechanisms cannot explain a time lag in the effect. Probably the time lag would in fact rule both of those mechanism out (In addition to the reasons noted above and below.)

I take it you've just eyeballed their charts, and see a phase lag? There does seem to be a small lag.

The authors acknowledge that there is time lag and reference another paper that confirms the time lag is real. The authors note the time lag is evident in their data and the independent radium 226 decay data.

The strawman explanation that the sun changes periodically in a matter that correlates with the sun-distance does not seem physically possible.


Returning to Fig. 4, we briefly explore the suggestion noted above of a possible phase shift of 1/R^2 relative to both the BNL and PTB data. Although this may be an experimental artifact arising from binning effects, etc., such a phase shift could also arise from other smaller contributions to periodic variations in neutrino flux. Possibilities for such contributions were explored in Ref. [17], where a search was made for short time variations in the observed flux at Super-Kamiokande arising from either the 7.25 degree inclination of the solar axis relative to the ecliptic, or from fluctuations in the temperature of the solar core.

A modulation of the neutrino flux arising from a coupling between a neutrino magnetic moment and a latitudinally inhomogeneous solar magnetic field [22] could also account for a possible phase shift. Although there is no compelling evidence at present for such short time variations at Super-Kamiokande[16, 17], the statistical power of the BNL, PTB, and similar data sets may prove to be a useful tool in the search for such effects. Yet another possible explanation for the apparent phase shift could be a seasonally-varying velocity-dependent effect similar to that observed by the DAMA/LIBRA collaboration [23].

In summary, we have presented evidence for a correlation between changes in nuclear decay rates and the Earth-Sun distance. While the mechanism responsible for this phenomenon is unknown, theories involving variations in fundamental constants could give rise to such effects. These results are also consistent with the correlation between nuclear decay rates and solar activity suggested by Jenkins and Fischbach [18] if the latter effect is interpreted as possibly arising from a change in the solar neutrino flux.


Comment:
As noted in my comment above, I believe there is a simpler explanation, although it has multiple fundamental implications. The explanation for the nuclear decay rate variance with sun-earth distance is the same as the explanation for the Pioneer velocity variance, and the intrinsic redshift hypothesis. The problem is to present the strawman explanation, there needs to be some preparation work to organize the other supporting observations and to layout the supporting logic.

hhEb09'1
2008-Aug-30, 02:49 PM
In reply to hhEb09'1's comment:

The authors acknowledge that there is time lag and reference another paper that confirms the time lag is real. The authors note the time lag is evident in their data and the independent radium 226 decay data.Yes, I see the passages now. I only scanned the article before--but why did you say the authors ignored the phase lag then? It looks like they mention it multiple times within the article.

That's why I figured you were basing the time lag upon the graphs themselves.

Jerry
2008-Aug-30, 03:02 PM
Note everyone (authors and comments in this thread) are ignoring that there is a clear observed phase lag for the effect. The effect lags the change in the sun-earth distance. As gravitational changes are per the GR theory at the speed of light and neutrinos also travel at near light speed, those mechanisms cannot explain a time lag in the effect. Probably the time lag would in fact rule both of those mechanism out (In addition to the reasons noted above and below.)

I don't think you can rule out gravity, and this might be the most important clue. - you are assuming the effect is a first order function. The solar rate-of-change in the gravitational field is highest between phases. If gravitational interactions with matter have a 'shear' function that can displace energy, the 'shear' rate could be greatest at an offset from the tidal peak.

(The measured rate changes are much greater than the changes predicted by GR, so it is a given that convention gravity is not a contributor.)

parejkoj
2008-Aug-30, 03:38 PM
I would think that background signals are very easy to correct for, by directly measuring those counts.

Not necessarily. If you have an experiment with a low background, say a count per minute or so, if there is a variation in the background over month-long timescales, how would you "easily" detect it? And this particular experiment ran for years, so how would you "directly measure" those counts over the same timescale? You can't just use a different detector, since their responses and variations will be different.


I haven't read the paper, but I can't believe an explanation that simple would not have been addressed by the authors. I'll check later this weekend.


They only discuss the radon background, and say "and in any case, the PTB data shown in Fig. 3 were corrected for background..." but don't describe how. It may be described in one of the references, since they are borrowing data from other groups.

borman
2008-Aug-30, 08:47 PM
I wonder if neutrino oscillation might figure into this with the solar flare connection. Could a Tau neutrino bath make for a change in decay rate compared to an electron neutrino bath? The Fermi lab was doing experiments to verify neutrino oscillation until funds were threatened. Monitoring the same samples at different places along the oscillation path might show if oscillation is involved.

Upon further reflection, it may be that I have this idea backwards. An unanswered question is how neutrinos can oscillate and yet move at light speed. The oscillation implies a rest mass which then would seem to preclude lightspeed movement.

Using the Anderson et al formula for the flyby anomaly, which may figure into the DAMA/LIBRA interpretation, one has :
Delta E/2E=K(cos(theta_i)-cos(theta_o))

Classically, the Delta E should be zero but a number of spacecraft seem to disregard this during flybys. The neutrinos have their lightspeed energy but any Delta E/c^2 might be interepreted as rest mass and imposed upon the carrier signal to give the oscillation.

So rather than suggesting that neutrino oscillation might be at the root of the decay anomaly, they may themselves be victims of a flyby anomaly.

VanderL
2008-Aug-31, 08:58 PM
Not necessarily. If you have an experiment with a low background, say a count per minute or so, if there is a variation in the background over month-long timescales, how would you "easily" detect it? And this particular experiment ran for years, so how would you "directly measure" those counts over the same timescale? You can't just use a different detector, since their responses and variations will be different.

They used different radionuclides, including "long-lived" standards to calculate ratio's.

As in other counting experiments, the
counting rate for 32Si was continually monitored in the same detector against a long-lived comparison standard, which in the BNL experiment was 36Cl (T1/2=301,000 yr).

By choosing enough radioactive material a vey high countrate versus background can be achieved, which would assure a vey low background influence.


They only discuss the radon background, and say "and in any case, the PTB data shown in Fig. 3 were corrected for background..." but don't describe how. It may be described in one of the references, since they are borrowing data from other groups.

They mention in the caption of figure 3
Note that the 1 sigma error bars for the PTB data lie within the data points themselves.

In other words, too small to plot, something that in my work I can only get when I enlarge the datapoints to ridiculous sizes :lol:.

So I see no room for much background contribution, which does nothing to help me understand what they have confirmed with this study. Would magnetic fields influence radiactive decay rates?

Cheers.

parejkoj
2008-Aug-31, 10:03 PM
By choosing enough radioactive material a vey high countrate versus background can be achieved, which would assure a vey low background influence.

But that's my point: if the background is very low, it will be difficult to identify or eliminate any periodic changes in the background rate. And such a periodic change, even at a low rate, could show up as such a variation in the signal.



In other words, too small to plot, something that in my work I can only get when I enlarge the datapoints to ridiculous sizes :lol:.

That doesn't say anything about how they did the background subtraction, just that they had a large countrate in general. The error bars are assuming they don't have a systematic, unidentified annual change in the background (funny, I'm sounding like the people who complain about WMAP's power spectrum, now!). This particular paper didn't discuss what they did to subtract the background, so I can't say if it missed something or not.

Incidentally, the second author of this paper will be giving a talk at our institution at the end of September. I expect he will get quite the grilling from our resident experimentalists... I'll report on what I hear.

William
2008-Sep-01, 01:59 AM
Originally Posted by William View Post
Note everyone (authors and comments in this thread) are ignoring that there is a clear observed phase lag for the effect. The effect lags the change in the sun-earth distance. As gravitational changes are per the GR theory at the speed of light and neutrinos also travel at near light speed, those mechanisms cannot explain a time lag in the effect. Probably the time lag would in fact rule both of those mechanism out (In addition to the reasons noted above and below.)

Originally Posted by Jerry View Post: I don't think you can rule out gravity, and this might be the most important clue. - you are assuming the effect is a first order function. The solar rate-of-change in the gravitational field is highest between phases. If gravitational interactions with matter have a 'shear' function that can displace energy, the 'shear' rate could be greatest at an offset from the tidal peak.

Time Lag Observation is Due to Say Systematic Errors?
A gravitational explanation would require that the time lag observation is in error which is possible. If the time lag is real the gravitational shear rate would require a time lag which does not seem possible as gravitational space-time changes occur at the speed of light.

I see what you mean concerning a gravitational shear, I was thinking only of a scalar field as that was the suggestion of the paper's authors, as the cause of the variance in the radioactive decay rate with earth-sun distance.

Based on the authors' comments and the discussions concerning the Pioneer anomaly, I have another mechanism which I would like to throw out.


Originally Posted by hhEb09'1: Yes, I see the passages now. I only scanned the article before--but why did you say the authors ignored the phase lag then? It looks like they mention it multiple times within the article.

Solar Charge Unbalance?
If the time lag is real and the radioactive rate effect is due to a scale field, the effect could possibly be due to the sun not being electrically neutral. I believe a net electric charge unbalance will directly alter the radioactive decay rate.

If the sun has let say a net positive charge, then there is a lag as the earth's ionosphere/atmosphere gains or losses charge to be equalized for the potential which is the correct balance for the relative earth-sun distance. The "equalized" potential changes depending on the earth-sun distance.

If you look at the end of the thread concerning Solar cycle 24 there is that data which supports extensive flash burns on the earth's surface (500,000 flash sites for example from New Jersey to Alabama.) at multiple locations in the Northern Hemisphere 12,900 kyrs ago. I have noticed a number of different anomalies (For example, there is a set of Skylab astronaut observations.) that would support charge movement from ionosphere to planet, in addition to large flashing/charge events at roughly 14,000 year periods. Those observations might support the hypothesis that the sun is not electrically neutral and that from time there is charge unbalance in the solar system.

Perhaps when the solar magnetic cycle is interrupted, the solar charge is no longer equalized by the magnetic ropes that move up from the radiative zone through the convection zone to the surface of the sun. During a solar magnetic cycle interruption charge builds up in the radiative zone, until there are a number of massive charge releases which will restart the solar magnetic cycle.

From the standpoint of the earth, the earth will try to equalize to the interrupted solar charge potential. When there is a sudden release of solar charge, there will be currents from the atmosphere/ionosphere to the planet's surface and as the earth re-adjusts to what is the normal potential when the solar magnetic cycle is active.

Jerry
2008-Sep-01, 04:42 AM
Implications for 14C Dating of the Jenkins-Fischbach Effect and Possible Fluctuation of the Solar Fusion Rate
Alvin J. Sanders



It has long been known that the 14C calibration curve, which relates the known age of tree
rings to their apparent 14C ages, includes a number of “wiggles” which clearly are not
experimental errors or other random effects...A reasonable interpretation of these wiggles is
that they indicate that the Sun’s fusion “furnace” is pulsating, perhaps for reasons similar to
that of the Cepheid variables, albeit under a very different regime of pressure and
temperature. If this speculation is correct, we are seeing the heartbeat of the Sun...

Rather speculative, but I think it compliments this thread quite well.

dgruss23
2008-Sep-01, 12:09 PM
Incidentally, the second author of this paper will be giving a talk at our institution at the end of September. I expect he will get quite the grilling from our resident experimentalists... I'll report on what I hear.

Great! I'll be very anxious to hear your thoughts on what he says. :)

dgruss23
2008-Sep-01, 12:18 PM
Implications for 14C Dating of the Jenkins-Fischbach Effect and Possible Fluctuation of the Solar Fusion Rate
Alvin J. Sanders


Rather speculative, but I think it compliments this thread quite well.

Here (http://arxiv.org/abs/0808.3986) is the article. It would be necessary to backtrack to the articles that discuss the wiggles in the C14 dating curves. It is well established that C-14 levels fluctuate with the solar cycle, but perhaps those fluctuations are much smaller than the wiggles discussed in the paper.

William
2008-Sep-01, 05:00 PM
I would be interested in hearing Sander's lecture concerning possible linkage of C14 levels to solar fusion levels. I wonder if Sander is familiar with the competing hypothesis. The evidence that the 200 year cycle is a solar magnetic cycle rather than a fusion cycle seems to be quite strong.

There are a series of papers that show the solar magnetic cycle has a 200 year cycle with harmonics (see papers linked to below) from the analysis of the dendrochonological record.

The driver for the solar magnetic cycle periodic variance is hypothesized to be solar motion about its barycentre which when there is a rapid change in direction, disturbs the tachocline. (The tachocline is a quiet region that separates the solar radiative zone from the convection zone and is the region where the solar magnetic ropes rise to the surface and form sunspots are hypothesized to be created.)

Based on current data it appears the sun is currently moving into a deep solar magnetic minimum. If you go to the solar cycle 24 thread there is a graph in one of the last comments that shows sunspot magnetic field strength from a paper by Livingston and Penn. Livingston and Penn have found that the sunspot magnetic strength of all sunspots created at particular point in time is now decreasing at 75 gauss per year and has dropped from 3000 gauss to 1931 gauss.

Now for the magnetic ropes to survive the trip through the turbulent convection zone they are hypothesized (Eugene Parker's mechanism.) to require a minimum strength of 10,000 gauss at the tachocline. As the magnetic ropes rise up through the convection zone they are broken into smaller pieces by turbulence in the convection zone. Time lapse analysis shows the pieces of magnetic ropes reconfigure on the surface of the sun to form sunspots.

Now it appears that the minimum strength of the magnetic ropes has dropped below the 10,000 gauss minimum, as there are no sunspots. If the magnetic ropes that are formed at the tachocline are less than 10,000 gauss, Parker's analysis indicated that they will be destroyed as they rise up through the convection zone.

The planet's temperature also follows this short term cycle.

The 200 year cycle has harmonics such that it shows a 2400 year cycle.


http://www.wsl.ch/forest/dendro2001/abstracts/ext33.pdf

Dendrochonological evidence of long - term variations in solar activity and climate

We carried out the spectral analysis of the content of radiocarbon for the last 8,000 years measured in rings of trees of known age (Stuiver and Becker 1993). It revealed the existence of several spectral harmonics: 2,400, 1200, 940, 710, 570, 505, 420, 360, 230, 210 years (Fig. 1). Fig.

http://www.ann-geophys.net/20/115/2002/angeo-20-115-2002.pdf


We have carried out power spectrum, time-spectrum and bispectrum analyses of the long-term series of the radiocarbon concentrations deduced from measurements of the radiocarbon content in tree rings for the last 8000 years. Classical harmonic analysis of this time series shows a number of periods: 2400, 940, 710, 570, 500, 420, 360, 230, 210 and 190 years. A principle feature of the time series is the long period of approx. 2400 years, which is well known. The lines with periods of 710, 420 and 210 years are found to be the primary secular components of power spectrum. The complicated structure of the observed power spectrum is the result of approx. 2400-year modulation of primary secular components.

Lepton
2008-Sep-01, 05:05 PM
Yee-haw! That certainly puts a crimp in the long held idea that radioactive decay is immutably constant!

Yee-haw, last time I checked correlation does not equal causation...Yee-haw.

William
2008-Sep-01, 05:24 PM
This comment is in follow-up to my last comment that the 200 year cycle in C14 is likely due to solar magnetic cycle changes rather than to solar fusion rate changes.

This is one of the papers that notes there is a correlation of past solar magnetic minimums with specific solar barycenter motion.

This paper published in 1987 is one of three papers that predicted a imminent solar magnetic cycle minimum.

http://www.springerlink.com/content/w57236105034h657/

“Prolonged minima and the 179-yr cycle of the solar inertial motion” by R. Fairbridge1 and J. Shirley


We employ the JPL long ephemeris DE-102 to study the inertial motion of the sun for the period A.D. 760–2100. Defining solar orbits with reference to the Sun's successive close approaches to the solar system barycenter, occurring at mean intervals of 19.86 yr, we find simple relationships linking the inertial orientation of the solar orbit and the amplitude of the precessional rotation of the orbit with the occurrence of the principal prolonged solar activity minima of the current millenium (the Wolf, Spörer, and Maunder minima). The progression of the inertial orientation parameter is controlled by the 900-yr great inequality of the motion of Jupiter and Saturn, while the precessional rotation parameter is linked with the 179-yr cycle of the solar inertial motion previously identified by Jose (1965). A new prolonged minimum of solar activity may be imminent.


In reply to Lepton's comment: Yee-haw, last time I checked correlation does not equal causation...Yee-haw.

Correlation is a necessary condition. Determining what is the hypothesized mechanism is the next step. The last is attempting to prove the hypothesis.

If it is a fact that radioactive decay rates changes based on the earth-sun distance, that fact needs an explanation.

Are you suggesting the radioactive decay rate variance with earth-sun distance is due to systematic measure effects?

Lepton
2008-Sep-01, 05:29 PM
Are you suggesting the radioactive decay rate variance with earth-sun distance is due to systematic measure effects?

I am not suggesting anything though I am saying correlation does not equal causation. Didn't my post say those exact words? If you or anyone can show me that nuclear decay rates (half-lifes) are anything more than an AVERAGE then maybe there is a question to be answered but until then this is senseless pursuit.

dgruss23
2008-Sep-01, 08:21 PM
Yee-haw, last time I checked correlation does not equal causation...Yee-haw.

It would be more accurate to say that the existence of a correlation between two variables does not guarantee there is a causal connection between those variables. In order for there to be a real causal relationship worthy of discussion you must at least have a scientifically plausible mechanism to account for the correlation. In the case of this paper the proposed mechanism is variations in neutrino flux.

VanderL
2008-Sep-02, 06:17 AM
But that's my point: if the background is very low, it will be difficult to identify or eliminate any periodic changes in the background rate. And such a periodic change, even at a low rate, could show up as such a variation in the signal.

Not if the countrate is very high. I believe the reported variation was on the order of 3 per thousand, increasing the countrate to several orders of magnitude above the background level would clearly null any influence.


That doesn't say anything about how they did the background subtraction, just that they had a large countrate in general. The error bars are assuming they don't have a systematic, unidentified annual change in the background (funny, I'm sounding like the people who complain about WMAP's power spectrum, now!). This particular paper didn't discuss what they did to subtract the background, so I can't say if it missed something or not.

Incidentally, the second author of this paper will be giving a talk at our institution at the end of September. I expect he will get quite the grilling from our resident experimentalists... I'll report on what I hear.

Thanks, I appreciate such a report, it seems an important observation, if it stands up to scrutiny.

Cheers.

antoniseb
2008-Sep-02, 10:21 AM
I'd like to point out that the paper's graph shows a correlation, but there is a phase shift, as though it is correlated to local outdoor temperature more than distance to the Sun or hours of light.

trinitree88
2008-Sep-02, 12:41 PM
Jenkins et al (http://xxx.lanl.gov/abs/0808.3283) find evidence that the rate of nuclear decay of Si-32 and Ra-226 has an annual variation that correlates with the Earth-Sun distance. They are not sure what the mechanism is for this correlation. One possibility they discuss involves the fine structure constant while the other is tied in with solar neutrinos.

dgruss. I'll suggest the coupling of neutrinos to neutrons via spin waves (magnons) which add the extra 30% momentum suggested by Leinson to cause supernovae to successfully go...(circa 1989)...and which incorporates the strength of the ambient B field in the numerical approximations, can in a small way contribute to a small but noticeable perturbation in radionuclides half-lives in weak fields. In essence creating "warmer" excited states in the nuclei which tunnel more quickly, or emit Betas more easily.
pete

see:http://adsabs.harvard.edu/abs/1989PZETF..49...65L

William
2008-Sep-02, 06:56 PM
Originally Posted antoniseb by: I'd like to point out that the paper's graph shows a correlation, but there is a phase shift, as though it is correlated to local outdoor temperature more than distance to the Sun or hours of light.

I believe the experiment has repeated in the Southern Hemisphere to confirm the time lag effect was not due to seasonal temperature changes.

antoniseb
2008-Sep-02, 07:43 PM
I believe the experiment has repeated in the Southern Hemisphere to confirm the time lag effect was not due to seasonal temperature changes.

There's no mention of such a repeat in the paper. The paper simply described collected data from other previous experiments.

William
2008-Sep-03, 01:49 AM
In reply to antoniseb,



Originally Posted by William View Post
I believe the experiment has repeated in the Southern Hemisphere to confirm the time lag effect was not due to seasonal temperature changes.

Originally Posted by antoniseb View Post
There's no mention of such a repeat in the paper. The paper simply described collected data from other previous experiments.

antoniseb, Your comment is correct. There was a latitude and a climate difference between the two different laboratories, but the experiments used different radioactive isotopes. Both sets of experiments found the radioactive decay rate varied with sun-earth distance and had a time lag.

Perhaps that finding does not definitively rule out temperature and climatic effects, but it at least makes it less likely something obvious was overlooked. I thought your suggestion of repeating the experiment in different locations (say in a deep mine) makes sense, as it is not completely obvious how that would affect the outcome of the experiment.


Moreover, the difference in latitude between BNL and PTB, as well as the difference in their climates, argues against an explanation of this correlation in terms of seasonal variations of climatic conditions such as temperature, pressure, and humidity etc., which could have influenced the respective detection systems. (my bold.) As an example, radon concentrations are known to fluctuate seasonally, as has been noted in Ref. [10], and it was suggested that the decay of 222Rn could lead to a seasonally dependent charge distribution on the experimental apparatus. However, this effect is extremely small given the low counting rates that typically arise from radon background [11], and in any case, the PTB data shown in Fig. 3 were corrected for background.

Comment:
If the forcing function was charge related, the earth mantel's is an insulator and there would be a long time delay for a change in surface charge to be observed. I would think a seasonal change of charge (assuming that mechanism) would not be observed. I found a couple of papers along the charge hypothesis line of thought.

There is a research satellite that was launched to gather data concerning the space charge movement from top of the earth's atmosphere to the ionosphere. The phenomena is called 'sprites'. There has been some research by NASA looking into field variances causing earthquakes and being use to predict earthquakes mention in that research. That type of research supports charge variance on the planet.

The tricky part for the charge hypothesis is at the sun to develop a mechanism and proof of charge variance.

BigDon
2008-Sep-05, 09:28 PM
Okay, mind boggled, check.

Jesus, I was waiting for somebody to shoot this down.

But if this floats passed Parekoj, George AND Trinitree without being reduced to tatters then I'm just stunned.

Nice find Dgruss! Who da' thunk it?

parejkoj
2008-Sep-25, 01:33 AM
Well, I saw Fischbach's talk today at the institution across the street (he's talking tomorrow at my university, but I figured I'd get a preview...).

First of all, he's a good speaker, which is nice to see. Plenty of physicists are terrible (or even just kinda bad and really boring) public speakers, so this is one thing he has going for him. But he had the same problem in the talk that the paper had: he essentially ignored all problems of instrumental background and calibration and jumped immediately into a discussion about what "new physics" could cause the measured effect.

It was rather odd to note that there were no significant questions about his methodology from the audience. There were even some astronomical instrumentalists there, so you'd think it would be on their minds...

I had quite a few questions, though I only asked one during the public question session--if this "decay rate" variation is real and due to something related to the distance from the Sun, Cassini's RTGs should easily show a significant decrease in power because the plutonium is decaying at a different rate. He said he's trying to get the data to find out, but I recall from when I was working for Cassini's INMS that the RTGs were working slightly better than expected in ~2004... and a post I made on BAUT back then confirms it! (http://www.bautforum.com/against-mainstream/9682-gravity-versus-young-earth-creationists-4.html#post185309)... Hmmm...

I'm going to have lunch with him tomorrow, watch while some of our professors sharpen their axes and then watch the talk again. I expect the question session to be much more lively tomorrow...

Jerry
2008-Sep-25, 03:47 AM
I had quite a few questions, though I only asked one during the public question session--if this "decay rate" variation is real and due to something related to the distance from the Sun, Cassini's RTGs should easily show a significant decrease in power because the plutonium is decaying at a different rate. He said he's trying to get the data to find out, but I recall from when I was working for Cassini's INMS that the RTGs were working slightly better than expected in ~2004... and a post I made on BAUT back then confirms it! (http://www.bautforum.com/against-mainstream/9682-gravity-versus-young-earth-creationists-4.html#post185309)... Hmmm...
...
The performance of the Pioneer and Voyager RTGs has also been 'better than expected'. HOWEVER, if the slower decay rate is real - all bets are off on the expected yield.

VanderL
2008-Sep-25, 03:06 PM
Well, I saw Fischbach's talk today at the institution across the street (he's talking tomorrow at my university, but I figured I'd get a preview...).

Thanks parejkoj, for reporting back to us.



First of all, he's a good speaker, which is nice to see. Plenty of physicists are terrible (or even just kinda bad and really boring) public speakers, so this is one thing he has going for him. But he had the same problem in the talk that the paper had: he essentially ignored all problems of instrumental background and calibration and jumped immediately into a discussion about what "new physics" could cause the measured effect.

It was rather odd to note that there were no significant questions about his methodology from the audience. There were even some astronomical instrumentalists there, so you'd think it would be on their minds...

I can think of at least one reason these questions weren't asked, the experiments "correct" for any background influence by increasing signal to noise to whatever level is needed. Another would be that the audience is too shy to ask? :)


I had quite a few questions, though I only asked one during the public question session--if this "decay rate" variation is real and due to something related to the distance from the Sun, Cassini's RTGs should easily show a significant decrease in power because the plutonium is decaying at a different rate. He said he's trying to get the data to find out, but I recall from when I was working for Cassini's INMS that the RTGs were working slightly better than expected in ~2004... and a post I made on BAUT back then confirms it! (http://www.bautforum.com/against-mainstream/9682-gravity-versus-young-earth-creationists-4.html#post185309)... Hmmm...

Actually, if I read the graphs in the paper correctly, the decay rate increases further from the Sun, which would make the Cassini observation make sense, right?


I'm going to have lunch with him tomorrow, watch while some of our professors sharpen their axes and then watch the talk again. I expect the question session to be much more lively tomorrow...

Great, hope to hear more details soon.

Cheers.

ngc3314
2008-Sep-25, 04:26 PM
I had quite a few questions, though I only asked one during the public question session--if this "decay rate" variation is real and due to something related to the distance from the Sun, Cassini's RTGs should easily show a significant decrease in power because the plutonium is decaying at a different rate. He said he's trying to get the data to find out, but I recall from when I was working for Cassini's INMS that the RTGs were working slightly better than expected in ~2004... and a post I made on BAUT back then confirms it! (http://www.bautforum.com/against-mainstream/9682-gravity-versus-young-earth-creationists-4.html#post185309)... Hmmm...


By th most amazing coincidence, this (http://arxiv.org/abs/0809.4248) just showed up on arxiv.org:

Searching for modifications to the exponential radioactive decay law with the Cassini spacecraft, by Peter S. Cooper.




Data from the power output of the radioisotope thermoelectric generators aboard the Cassini spacecraft are used to test the conjecture that small deviations observed in terrestrial measurements of the exponential radioactive decay law are correlated with the Earth-Sun distance. No significant deviations from exponential decay are observed over a range of 0.7 - 1.6 A.U. A 90% Cl upper limit of 0.84 x 10^-4 is set on a term in the decay rate of Pu-238 proportional to 1/R^2 and 0.99 x 10^-4 for a term proportional to 1/R.


As nearly as I can tell, the restricted range in heliocentric distance comes from using the data in the early part of the mission where it crossed R-1 AU five times, allowing an independent stability check of everything else in power measurement.

parejkoj
2008-Sep-25, 05:52 PM
Heh... I was just about to post that. Pretty amazing coincidence, though I had nothing to do with it. Really! Fischbach mentioned it during our lunch conversation. Pretty conclusively rules out any effect on Pu decay.

But...

Fischbach's counter is that the 226Ra alpha-decay products undergo beta decay with ~minute half-lives, while 238Pu's alpha-decay products have million year half-lives (Uranium). Thus, if the effect is on beta decay and not alpha decay, they could have been seeing the signal from the products, not the original decay and 238Pu wouldn't show it, because of the long decay time for the products.

Plausible, but I'm still not convinced that the "signal" here isn't just something mundane. I still think the plot vs. 1/R2 is a red-herring: it's an annual correlation, and there are a million things that vary on that timescale. I made a quick plot of the mean monthly temperature near Brookhaven (one of the labs that the original data came from) for the period of the 32 experiment, and it lines up nicely with the measurements. The experiment supposedly was done in an air-conditioned room, but still... Jumping straight to "new physics" doesn't seem warranted, yet.

But who am I to speak?

Jerry
2008-Sep-26, 12:05 AM
One would expect a common mechanism, one effecting both alpha and beta decay; and the effect would have to be extremely small - or it would have been picked up a century ago...mmm...unless the sensitive balances they used were thrown proportional curves. That's the hard part about looking for cracks in modern physics - the seams are there, but they are painfully small, and it is difficult to tell if we are at observational limits or limited by our observational miscues.

borman
2008-Sep-26, 05:04 AM
If only beta but not alpha, does this rule out modulation of universal constants then?

Jerry
2008-Sep-29, 03:25 AM
Not quite. Since alpha particles are much more massive than beta, you could have a universal constant constant that is also proportional to mass -kt/m type of thing...which is of the same general form as the GR mass relationships.

JukriS
2008-Sep-29, 05:14 AM
Because neutrinos expanding and emit energywaves!

timb
2008-Oct-21, 07:55 AM
Evidence against correlations between nuclear decay rates and Earth-Sun distance (http://arxiv.org/abs/0810.3265)
Authors: Eric B. Norman, Edgardo Browne, Howard A. Shugart, Tenzing H. Joshi, Richard B. Firestone
(Submitted on 17 Oct 2008)

Abstract: We have reexamined our previously published data to search for evidence of correlations between the rates for the alpha, beta-minus, beta-plus, and electron-capture decays of 22Na, 44Ti, 108Agm, 121Snm, 133Ba, and 241Am and the Earth-Sun distance. We find no evidence for such correlations and set limits on the possible amplitudes of such correlations substantially smaller than those observed in previous experiments.

ASEI
2008-Oct-21, 08:52 AM
Originally Posted by trinitree88
dgruss. Radioactive decays occur at different rates within the floors of a high rise office building from GR considerations....and there is a differential neutrino flux between them.
They also have extended half-lives due to SR...muons in accelerator labs...that experience a different neutrino flux than their sitting counterparts.
Solar proximity changes both GR considerations..(sun's well)...and SR considerations...Keplerian velocity increase....as well as the ambient neutrino fluxes.
Not a surprise. pete

Free neutrons have a dramatic change in radioactive decay rates as ambient magnetic fields approach 1011 to 1013 Gauss...on the order of strength of many pulsars.

see:
http://www.nature.com/nature/journal.../222649b0.html

ans see:
Question about neutron stars

or:Neutrons are unstable; how come neutron stars are stable?

But both measurements were made in Earth's surface reference frame, right? We only expect variation in decay rates under GR and SR if we're measuring the matter decaying in a different reference frame, such as the rate measured on an orbiting spacecraft as measured by Earth, or vice versa.

That there is some other variation in this scenario suggests a different mechanism.

ASEI
2008-Oct-21, 09:08 AM
Evidence against correlations between nuclear decay rates and Earth-Sun distance
Authors: Eric B. Norman, Edgardo Browne, Howard A. Shugart, Tenzing H. Joshi, Richard B. Firestone
(Submitted on 17 Oct 2008) I read it, but I still don't see where they produce anything that removes the possibility for an effect somewhere.


It is interesting to note that in the work of Alburger et al.1 a very statistically significant annual
variation in the ratio of count rates of 32Si/36Cl was observed (see Fig. 4 of Ref. 1). These authors
could not identify a mechanism that could quantitatively explain these observations. However, in the
work of Siegert et al.2, where a similar amplitude annual variation in the count rate of 226Ra was
observed (see Fig. 1 of Ref. 2), when the ratio of observed count rates of 154Eu/226Ra was examined,
the annual variations disappeared (see Fig. 3 of Ref. 2). These authors attributed the annual
variations observed from the decays of a single source to a yearly variation in the performance of
their experimental equipment that cancelled out in the ratio. So we have multiple independent pieces of experimental equipment with the same periodic varying of performance? And the way they've been cancelling it out is to relate one decay rate with the decay rate of something else?

I think there's still room for an actual effect here, whether in something that makes decay rates happen more often, or some common effect on all our measuring equipment!

borman
2008-Oct-24, 01:01 AM
In the paper, they do not consider that the effect could act universally over the different routes of decay and expect that beta decay should be different from alpha decay. Within this view they find the null hypothesis to be favored. But the analysis is blind to the possibility that the effect is universal.

"If the Jenkins proposal were correct, it is very unlikely that the alpha, beta-minus, beta-plus, and electron-capture decays of all radioactive isotopes would be affected in quantitatively the same way. Thus the ratios of counts observed from two different isotopes would also be expected to show annual variations."