Scientists say they have found a ‘fifth force of nature’

The distance between the Earth and the Sun has no influence on the decay rate 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 solar neutrinos 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 radioactive isotope 36Cl which showed seasonal variations 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."


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Melvin Schwartz and the Discovery of the Muon Neutrino
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Melvin Schwartz
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Brookhaven National
Laboratory
Melvin Schwartz was the co-winner of the 1988 Nobel Prize in Physics "for the neutrino beam method and the demonstration of the doublet structure of the leptons through the discovery of the muon neutrino". 'In 1962, Schwartz, with Leon Lederman and Jack Steinberger … discovered the muon neutrino at the Alternating Gradient Synchrotron (AGS), the then brand-new accelerator at the U.S. Department of Energy's Brookhaven National Laboratory. …

First coming to Brookhaven in 1955, Schwartz performed his Ph.D. thesis research through 1956 at the Laboratory's first accelerator, the Cosmotron. While finishing his thesis, he was employed by the Laboratory from 1956-58.

Returning to Columbia University, Schwartz continued to do research at Brookhaven, working at the AGS from 1958-63. After relocating to Stanford University in 1966, he maintained his research ties with Brookhaven.

In 1970, Schwartz founded a major computer-security company, Digital Pathways, Inc., in Mountain View, California. Later, Nicholas Samios, former Brookhaven Lab Director and currently head of the BNL-RIKEN Research Center, encouraged Schwartz to return to physics. He did so in 1991, returning to Brookhaven Lab as Associate Director for High Energy and Nuclear Physics. …

Melvin Schwartz was a member of the National Academy of Sciences and a fellow of the American Physical Society (APS). He received the Hughes Prize from the APS in 1964.'1

1 Edited excerpt Nobel Laureate Melvin Schwartz … Co-Discovered the Muon Neutrino at Brookhaven Lab in 1962
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