Old textbook knowledge reconfirmed: Decay rates of radioactive substances are constant

October 10, 2014
Measurements of the decay of the chlorine isotope 36Cl Between 2009 and 2013, scientists of the Physikalisch-Technische Bundesanstalt and of Ohio State University measured – with a time delay – the standardized activity, i.e. the radioactive decay, of 36chlorine. Whereas the American measurement results vary periodically, this is not the case with the PTB values. The blue curve illustrates the distance between the Earth and the Sun (presented as the reciprocal square of the distance in the astronomic unit AE).

Physikalisch-Technische Bundesanstalt (PTB) researchers refute the assumption that the decay rate of some radioactive nuclides depends on the distance between the Earth and the Sun.

The distance between the Earth and the Sun has no influence on the of radioactive chlorine. You could ask: "And why should it anyway?", because it is well known that the decay of radionuclides is as reliable as a Swiss clock. Recently, US-American scientists, however, attracted attention when they postulated that the decay rate depends on the flow of and, thus, also on the distance from the Earth to the Sun. Their assumption was based, among other things, on older measurement data of the Physikalisch-Technische Bundesanstalt (PTB). PTB researchers have now definitively refuted the assumption of the Americans.

The half-life of radioactive isotopes, i.e. the period in which half of all atomic nuclei have decayed, is regarded as invariably stable. In the case of the carbon isotope 14C, this period amounts, for example, to 5700 years. This property is, among other things, made use of for the dating of archeological findings. There was great excitement when a group of US-American scientists recently published measurement data of the isotope 36Cl which showed and explained this with the influence of solar neutrinos. All the more since billions of neutrinos from the Sun hit every square centimetre of the Earth every second and remain almost ineffective (they penetrate the Earth as if it weren't there).

Scientists of the Physikalisch-Technische Bundesanstalt have now carried out new measurements and have published their results in the journal "Astroparticle Physics". For three years, they checked the activity of samples with 36Cl in order to detect possible seasonal dependencies. Whereas the US-Americans had determined the count rates with gas detectors, PTB used the so-called TDCR liquid scintillation method which largely compensates disturbing influences on the measurements. The result: The measurement results of PTB clearly show fewer variations and do not indicate any seasonal dependence or the influence of solar neutrinos. "We assume that other influences are much more probable as the reason for the observed variations", explains PTB physicist Karsten Kossert. "It is known that changes in the air humidity, in the air pressure and in the temperature can definitively influence sensitive detectors."

Meanwhile, the data of another measurement series − this time for the strontium isotope 90Sr − have been evaluated and submitted for publication. Here too, even sophisticated analyzing methods give no indication of seasonal variations. It can thus be assumed that an influence of solar neutrinos on the does not exist − at least not in the order of magnitude postulated.

Explore further: Research shows radiometric dating still reliable (again)

More information: Karsten Kossert, Ole J. Nähle: "Long-term measurements of 36Cl to investigate potential solar influence on the decay rate." Astroparticle Physics 55 (2014) 33-36

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23 comments

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julianpenrod
1.3 / 5 (15) Oct 10, 2014
Among other things, to begin with, the graph is a fraud. The distance from the sun of a planet in an elliptical orbit does not proceed in a sinusoidal curve! The greater speed at perihelion and the lower speed at aphelion produce a curve more like that of a bouncing ball, a series of parabolas, with sharper, pointed curves at the low points where the parabolas join. Also, note the reference to equipment being vulnerable to surroundings. That sounds like an admission that the scintillation device cannot necessarily be trusted either. There seems no reason for Geiger counters not to be adequate for measurement. This method and its results are a fraud. It should be mentioned, too, it's not the closeness of the sun. The direction of the earth's movement through space, the effective aether, changes decay rates, just as it does the perceived velocity of light, as with the real but denied results of the Michelson-Morley Experiment.
omatwankr
1 / 5 (5) Oct 10, 2014
For 3 years Vs
"based on a Geiger-Mueller gas detector, which is a robust detector system with very low susceptibility to environmental changes. A clear annual variation is evident in the data, with a max relative count rate observed in Jan/Feb, and a min relative count rate observed in Jul/Aug, for seven successive years from July '05 to June '11. This annual variation is not likely to have arisen from changes in the detector surroundings,"

As well as a unusually weak solar max...

maybe they should have run both types of experiment simultaneously?

and
"On Dec 13, 06, 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."

om out
omatwankr
1 / 5 (4) Oct 10, 2014
fortranfixer
1 / 5 (8) Oct 10, 2014
This article is anti-American and perhaps racist. I have never read another article that identified the country of origin of the dissenters multiple times.
Vietvet
4.6 / 5 (11) Oct 10, 2014
This article is anti-American and perhaps racist. I have never read another article that identified the country of origin of the dissenters multiple times.


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TEP320
Oct 10, 2014
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TEP320
Oct 10, 2014
This comment has been removed by a moderator.
TEP320
Oct 10, 2014
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axemaster
5 / 5 (9) Oct 10, 2014
What I would really suggest here is to forget any creativity and do the exact replication of original observations of Ohio university with (using of) G-M counter. This is because the problem could be hidden not in dependence of speed of decays to neutrino flux, but in dependence of sensitivity of detectors to neutrino flux. We should simply check them both.

Sorry but that's not how the experiment works. The detectors are completely insensitive to neutrinos, it's only the radioactive isotopes that had any chance of being affected.
Captain Stumpy
4.4 / 5 (7) Oct 10, 2014
Sorry but that's not how the experiment works. The detectors are completely insensitive to neutrinos, it's only the radioactive isotopes that had any chance of being affected.
@Axe
in case you hadn't noticed... TEP320 and Tec12 are the latest Zephir sock puppets since castro got the axe

it is far more likely that he doesn't understand what you said than anything... sorry

Do you, by any chance, have the above study?
I found the news release but no study...

OZGuy
5 / 5 (6) Oct 11, 2014
Captain
Believe this may be related:

Disproof of solar influence on the decay rates of 90Sr/90Y
Karsten Kossert and Ole J. Nähle
Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig, Germany
http://arxiv.org/...2493.pdf

Eikka
5 / 5 (7) Oct 11, 2014
Among other things, to begin with, the graph is a fraud. The distance from the sun of a planet in an elliptical orbit does not proceed in a sinusoidal curve! The greater speed at perihelion and the lower speed at aphelion produce a curve more like that of a bouncing ball, a series of parabolas, with sharper, pointed curves at the low points where the parabolas join.


Only if the oribit is very very eccentric like that of a comet.

Earth's orbit around the sun is circular enough that it produces a nearly perfect sinusoid.

The eccentricity factor of 0 represents a perfectly circular orbit and 1 is a parabolic escape orbit. Earth's eccentricity is 0.0167. Halley's comet is 0.967.

TEP320
Oct 11, 2014
This comment has been removed by a moderator.
Captain Stumpy
4.2 / 5 (5) Oct 11, 2014
Captain
Believe this may be related:

Disproof of solar influence on the decay rates of 90Sr/90Y
Karsten Kossert and Ole J. Nähle
Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig, Germany
http://arxiv.org/...2493.pdf

@OZ
Thank you OZ
I am downloading it now to read

I really appreciate it
axemaster
5 / 5 (9) Oct 11, 2014
The detectors are completely insensitive to neutrinos, it's only the radioactive isotopes that had any chance of being affected
This is exactly what I would like to have checked independently. Do you have source of it?

My source is that I did radiation detection / particle physics in college. These detectors are capable of not only registering the impact of a high-energy decay particle, they are also measuring its energy. When they do this experiment, they are only looking at the specific decay energy of the isotope, nothing else. Even if neutrinos were somehow interacting with the detector itself (or something else nearby), that interaction would get ignored since it wouldn't be at the right energy.
katesisco
1 / 5 (7) Oct 11, 2014
The radiation decay rates may vary. I suspect the sun. During the brief period called the 'delayed' solar reversal the sun emits from the Equator. This is a different energy than from the poles. This very brief energy is tight, controlled, synchronized, as opposed to polar emitted energy that is loose,disorganized, less powerful.
Experiments during the 'delayed' solar reversal find astonishing results but alas, they cannot be duplicated afterwards. We search in vain for the Philospher's Stone and it will never be found.
TEP320
Oct 11, 2014
This comment has been removed by a moderator.
axemaster
5 / 5 (8) Oct 11, 2014
TEP, no offense, but your question doesn't make sense. The sensitivity of the detector doesn't change at all as a result of incoming particles, unless you saturate it (have events occurring inside the detector dead time). Nobody is going to check for such an effect, it's just not how the detector/experiment works.

Also, I wasn't making an assumption - that's the standard way of operating detectors.
TEP320
Oct 11, 2014
This comment has been removed by a moderator.
TEP320
Oct 11, 2014
This comment has been removed by a moderator.
barakn
4.6 / 5 (9) Oct 12, 2014
Am I the only person on the world, which thinks about consequences of experiments? If the neutrino flux is suspected to be a culprit, what prohibits the scientists to check it with distance from reactor?

Oh look, the experiment has already been done. The sun is a nuclear reactor, and there's no signal from it in this data as we move closer and farther from it. I expect you to be touting the previous experiments and ignoring this one within days, Zephir, because of the deep state of denial you are in.
LibertyKrueger
1 / 5 (5) Oct 12, 2014
If anyone's interested, I've been developing a new model for the process responsible for generating the particle structure that also includes the mechanism driving the atomic decay and transmutation processes. I'd be happy to go over the details here for anyone who wants me to.
omatwankr
1 / 5 (3) Oct 13, 2014
Evidence of Solar Influences on Nuclear Decay Rates
http://moriond.in...bach.pdf

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