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The SArov Tritium Neutrino Experiment (SATURNE), will study neutrino–atom collisions at unprecedentedly low energies for neutrino scattering experiments. A high-intensity tritium source of electron antineutrinos will be employed, with a total tritium mass of at least 1 kg (about 10 MCi) and possibly up to 4kg (about 40 MCi). The goal of SATURNE is to provide the first experimental evidence of coherent elastic neutrino-atom scattering and to search for the neutrino magnetic moment. It is expected that the detection and measurement of the elastic neutrino–atom interaction channel will be achieved using a 1–m³ liquid He-4 detector in a superfluid state. With five-year data from this detector, one will be able to probe the neutrino magnetic moment at a level of ${\mu }_{\nu }\sim 10^{-13}{\mu }_B$, which is an order of magnitude better than the world-leading upper limits. SATURNE will also study the ionization channel of neutrino-atom scattering. To this end, a cryogenic 4-kg Si crystal detector and a low-temperature 14-kg SrI₂(Eu) scintillation detector are being developed. Both detectors will have record low energy thresholds for their respective detector types. They are expected to achieve a sensitivity to the electron-antineutrino ${\mu }_{\nu }$ value of the order of $\sim 10^{-12}{\mu }_B$ already after one year of taking data.

On August 24, 2023, the Fukushima-1 nuclear power plant began dumping liquid radioactive waste into the ocean. It is planned to release water containing 22 TBq of tritium per year. This caused an outcry from the public and governments in many countries. A large amount of tritium is dumped into the ocean by nuclear fuel processing plants in France, Great Britain, and other countries. Tritium activity in fish near Cardiff reached 50,000 Bq/kg. Tritium differs from other technogenic radionuclides in that it is a part of tritium water. It can easily evaporate from the water surface and be carried by atmospheric currents to any distance. Therefore, any pollution of the ocean with tritium will quickly lead to contamination of soil, plants, and human food. In the Chelyabinsk region, unique conditions have developed for studying the process of atmospheric transfer of tritium from the surface of a technological reservoir to the surrounding area. The content of tritium in sediments and stagnant water bodies was estimated. We calculated the multiple correlation coefficients of tritium activity in water with the distance from the emission source and the deviation of the azimuth from the direction to the north. The transition of tritium into river and underground water was also studied. A regression equation was calculated for the dependence of the limiting level of ³H contamination of drinking water on the distance from the source of contamination. Correlation coefficients were calculated between the specific activity of radionuclides in river water and the amount of precipitation for the decade preceding sampling, activity and the sum of temperatures per decade, and activity and hydrothermal coefficient.

It has been reported by the present authors that introduction of water vapor to the purge gas can give quick decontamination of tritium from the surface of various materials through the isotope exchange reaction between water vapor in the gas phase and tritium on the surface. At collection of contaminated wastes with tritium, it is required by regulation to know the amount of tritium trapped to surface and bulk of disposal materials. However, it is difficult to measure the amount of tritium on the surface of materials such as tritium gas cylinder or pipes and reaction vessels in a tritium handling system. In this study, several experiments were performed applying the isotope exchange reaction between water vapor in the gas phase and tritium in the surface water to estimate the amount of tritium on the inner surface of used tritium gas cylinder made of aluminum alloy, and the results obtained from these experiments were compared with result of the smear method. Observed value for the amount of tritium on the surface of the aluminum alloy was similar to the value estimated using the trapping capacity of water on aluminum obtained by our previous experimental results. It is confirmed that injection of a little amount of water to the system makes it possible to extract whole tritium trapped on the inner surface of gas cylinder, though the smear method could not give quantitatively reliable results for measure the amount of tritium on the surface.

In-reactor tritium release experiments using the fast neutron source reactor “YAYOI” of the University of Tokyo were carried out in the temperature range of 673 to 873 K. The main chemical form (more than 99%) of released tritium was HT or T₂ irrespective of the H₂ concentration in He purge gas. The mass transfer coefficient increased with increasing hydrogen pressure in He purge gas up to 100 Pa at 873 K. The mass transfer coefficient for tritium from Li₂₀Sn₈₀ to pure hydrogen as the purge gas obeyed the following temperature dependence: K_D [m/s] = 2.82×10^-4exp(-27.2 [kJ/mol] / RT).

This article summarizes preparations at the University of Washington for a precision measurement of the mass ratio of H-3 (tritium) to He-3 with a new Penning trap mass spectrometer. This work will be continued at the Max-Planck-Institute for Nuclear Physics in Heidelberg in the Division of Stored and Cooled Ions. Only preliminary ion observations were performed in Seattle, but the target mass uncertainty for the measurement techniques under development is 1 part in 10¹¹.