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Hans_Leuenberger

Hans Leuenberger

University of Basel

Blockage Of The First Excited State Of 198hg
2nd Intl. Symp. on Technological Innovations in Medicine for Sustainable Development

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Abstract:

A 197Au solution with bi-distilled water was prepared using a single gold electrode, connected to a special oscillator with a sinewave voltage of 50 Hz at 160 V. It was known that it was not possible to detect gold in such a solution by chemical analysis at room temperature. Thus, neutron activation analysis (NAA) by creating 198Au seemed to be the method of choice for detecting the missing gold. 198Au is a b emitter that decays to an exited state of 198Hg nucleus, subsequently emitting a g photon of 411.8 keV, that can easily be detected. For this purpose, three solutions were prepared: Sample 0: 100 ml of water as zero-reference in case of impurities. For samples I and II, 200 ml of the same water were treated by a single electrode for 16 hours. Immediately after the treatment, the 200 ml were split into two samples perfectly mixed: sample II, i. e. 100 ml of the treated water was heated above 60°C, sample 0, had been heated before, and sample I, i. e. 100 ml of the treated but not heated water. All 3 samples together were exposed to a flux of thermal neutrons. Result: only the treated and warmed sample II showed the typical peak of g photons with the energy 411.8 keV. Samples 0 and I did not show any trace of gold. Sample I, as well as the other samples, were kept at room temperature for 11 days. The other samples behaved as expected. After a delay of 11 days, sample I was heated above 60°C. Interestingly, no g - photon was detected at 411.8 keV and after a second NAA (on the same, i. e. 11th day) no trace of Au was present anymore. A tentative theoretical explanation of this phenomenon is given by assuming that water can be considered as a semiconductor. Thus, also a photonic band gap can be expected. In other words, and in this context, the 411.8 keV g - rays were localized, if the temperature of the solution is kept below 60°C. This hypothesis is validated by the experimental results, since after heating up sample I above 60°C a mirrorless lasing happened. The fact that no trace of gold was visible is the proof of concept, that the remaining 197Au nuclei show a photonuclear reaction 197Au (g, n) 196Au decaying rapidly into 196Hg. However, in a first step the 198Au (g, n) 197Au reaction occurred leading to a reversal of the 197Au (n, g) 198Au reaction. In other words, the photonuclear reaction excited the collective movements of the neutrons and protons of the 197Au nucleus leading to giant resonances, and to the ejection of a neutron. In a second experiment the gold electrode was activated by exposure to thermal neutrons. Very similar results were obtained with the exception that between 15% to 20% of the unheated sample showed the 411.8 keV transition.