Topic: Can nuclear decay rates vary?

[Nemesis]

Link to full article

So that makes it hard to explain the curious periodic variations in the decay rates of silicon-32 and radium-226 observed by groups at the Brookhaven National Labs in the US and at the Physikalisch-Technische Bundesandstalt in Germany in the 1980s.

Today, the story gets even more puzzling. Jere Jenkins and pals at Purdue University in Indiana have re-analysed the raw data from these experiments and say that the modulations are synchronised with each other and with Earth’s distance from the sun. (Both groups, in acts of selfless dedication,  measured the decay rates of siliocn-32 and radium-226 over a period of many years.)

In other words, there appears to be an annual variation in the decay rates of these elements.

It turns out, that the notion of that nuclear decay rates are constant has been under attack for some time. In 2006, Jenkins says the decay rate of manganese-54 in their lab decreased dramtically during a solar flare on 13 December.

I wonder if this could have anything to do with why sustained fusion has not been achieved.  Could there be a missing element in reactors compared to within a star?  Something that changes the way the nucleus behaves.

[NJAntman]

Oh great! Decay is supposed to be "random" as it is now. They have to throw in cycles too. 

I think my next choice of employment will have to be customer service orientated. At least the randomness of customer behaviour can be pinned on the "a-hole" factor.

[Nemesis]

Seems that there is some confirmation.

Link to full article

On Dec 13, 2006, the sun itself provided a crucial clue, when a solar flare sent a stream of particles and radiation toward Earth. Purdue nuclear engineer Jere Jenkins, while measuring the decay rate of manganese-54, a short-lived isotope used in medical diagnostics, noticed that the rate dropped slightly during the flare, a decrease that started about a day and a half before the flare.

If this apparent relationship between flares and decay rates proves true, it could lead to a method of predicting solar flares prior to their occurrence, which could help prevent damage to satellites and electric grids, as well as save the lives of astronauts in space.

The decay-rate aberrations that Jenkins noticed occurred during the middle of the night in Indiana – meaning that something produced by the sun had traveled all the way through the Earth to reach Jenkins' detectors. What could the flare send forth that could have such an effect?

Jenkins and Fischbach guessed that the culprits in this bit of decay-rate mischief were probably solar neutrinos, the almost weightless particles famous for flying at almost the speed of light through the physical world – humans, rocks, oceans or planets – with virtually no interaction with anything.

Then, in a series of papers published in Astroparticle Physics, Nuclear Instruments and Methods in Physics Research and Space Science Reviews, Jenkins, Fischbach and their colleagues showed that the observed variations in decay rates were highly unlikely to have come from environmental influences on the detection systems.

This could be used as a solar flare predictor too. 

[Capt. Mike]

Nick, it's been a while since I went to Radiac school...but I seem to remember that the instructor said decay was "constantly random"...makes sense, right?


Mike

[Bonk]

I do not doubt that nuclear decay rates can be modified. There is nothing we cannot do. Nothing.

That said, there are numerous possible interferences in the measurement of radioactivity. I haven't looked it up but I'm curious what modes of decay are involved with these isotopes and how are they being measured and in what environment.

I have this sneaking suspicion that they have detected seasonal/solar variation in Compton background and that anti-coincidence detection techniques may cause the effect to disappear.

I guess it really depends on the mode of decay. To really comment intelligently I'd have to look them up and read the papers.

[marstone]

Nick, it's been a while since I went to Radiac school...but I seem to remember that the instructor said decay was "constantly random"...makes sense, right?


Mike

Now this might show that "constantly random" isn't really random, they just didn't know why it was not constant.  They were just to close to the subject to see the pattern.

[NJAntman]

Yea, "constantly random" is a bizarre term. Kind of like how refresher training every year is technically boring.

What is worse are the hookey looking graphics the instructors put into slide-shows, a PhD trying to show how smart they are having figured out MS clip-art.

[Capt. Mike]

Yea, "constantly random" is a bizarre term. Kind of like how refresher training every year is technically boring.

What is worse are the hookey looking graphics the instructors put into slide-shows, a PhD trying to show how smart they are having figured out MS clip-art.

This I understand..especially after finishing my 37th annual CPR training..I don't know who was bored the most...me, or the instructor

Mike

[Nemesis]

Assume that nuclear decay can be controlled. 

Damp it in a missile silo and the warhead lasts longer. Enhance it in a warhead and you can achieve critical mass at a lower level.

Enhance it at long range and blow the enemy missiles in their silos.  (Think Iran and N. Korea )

Used in a reactor you can get more power from less reactive fuel.  Maybe even from elements not normally radioactive. 

Nuclear rockets for launch (using normally not radioactive fuel) that even if it crashes spreads no radiation.

[Kreeargh]

Can nuclear decay rates vary?
Answer ? Yes it is all about the fuel used.   
The proper fuel used the perfect reaction can result.

[FA Frey XC]

I do not doubt that nuclear decay rates can be modified. There is nothing we cannot do. Nothing.

Umm, hate to disagree with you, but I can think of a couple things RIGHT NOW that we can't do, Bonkster.

The original article that Nemesis posted a link to basically is introducing an issue where radioactive decay is set to a constant. For example, when you measure the decay of a radioactive element, it is not suppose to change. This is why we call it a "constant". The issue is that we've found evidence of variences in said decay that we thought previously shouldn't be there

What the kicker was even more was that it seemed to be almost instantaneous, IE the solar flares that seemed to coincide with the variances didn't take into account the typical delay you see with light reaching the earth:

"On Dec 13, 2006, the sun itself provided a crucial clue, when a solar flare sent a stream of particles and radiation toward Earth. Purdue nuclear engineer Jere Jenkins, while measuring the decay rate of manganese-54, a short-lived isotope used in medical diagnostics, noticed that the rate dropped slightly during the flare, a decrease that started about a day and a half before the flare."

Some attribute it to solar neutrino's - but that's also questionable.. how does something that has almost no mass, and never interacts with physical matter, well, interact with energy states?

Regards,

[stoneyface]

not to derail the discussion here but this is exactly the kind of discussion that i wish would start in my forum. i posted this article 4 days ago and didn't get one response on it. please feel free to have this kind of discussion there as well.

[Nemesis]

I wonder if this effect could be measured in the nuclear power packs of long distance space probes?  I'm thinking specifically the 3 that are off course far out at the edge of the solar system. 

The article is assuming that it is neutrino based (with speculation of a brand new particle).  But what if it is more based on gravity?  The closer to the sun the more intense the gravity field.  Variations in solar gravity can occur due to matter flows inside the Sun or with coronal emissions.  The probes far out would be at a minimal level of gravitational intensity and any change would be weaker and possibly delayed compared to it on the Earth.


Just speculation. 

[NJAntman]

I was toying with the idea of bringing this story up with our lab supervisor. We use open-air irradiators to calibrate our radiac meters. At the strengths/distances/tolerane involved I'm almost certain variation in decay rates wouldn't make any difference for us but knowing about it would force him to write up several revisions in certain ISO procedures.

Spring it on him a week before his vacation a week before SOP revisions are due, priceless:knuppel2: 

[Bonk]

Of course... right now... I mean in geologic timescales if we can at least manage that kind of survival.

Problem with this whole discussion is that our primary time standard is itself based on a nuclear decay rate.

Perhaps the move from actual physical primary standards to ones based in nature was not such a good idea?

(meter defined by light, time defined by nuclear decay...)

I love tautologies. They define how we think. Or rather are a result of the tautology of matter unable to comprehend itself?

[Nemesis]

Link to full article

Researchers from NIST and Purdue tested this by comparing radioactive gold-198 in two shapes, spheres and thin foils, with the same mass and activity. Gold-198 releases neutrinos as it decays. The team reasoned that if neutrinos are affecting the decay rate, the atoms in the spheres should decay more slowly than the atoms in the foil because the neutrinos emitted by the atoms in the spheres would have a greater chance of interacting with their neighboring atoms. The maximum neutrino flux in the sample in their experiments was several times greater than the flux of neutrinos from the sun. The researchers followed the gamma-ray emission rate of each source for several weeks and found no difference between the decay rate of the spheres and the corresponding foils.

The article claims that this proves that there is no variation.  I see some problems with this proof.  First it makes the assumption that it neutrinos are the only potential cause but that was only speculation.  Second it uses different radioactive materials and assumes that all react the same.  It is highly possible that if there is any basis in it that different materials would react differently.  The test should have used one of the materials that already was allegedly varying.