At present, two nuclear research installations are being built at the premises of these institutes: the Multipurpose Fast Research Reactor (MBIR) in Dimitrovgrad and Neptune Pulsed Fast Reactor in Dubna.
MBIR is being built primarily for applied purposes. It will be used to evaluate novel materials and fuels, and to see how various types of reactors would function under the emergency operation modes. MBIR is also needed for the production of isotopes and for the performance of other practical tasks.
Neptune reactor is being designed to aid in deep fundamental research in the field of nuclear physics.
“Pre-project work is currently underway to clarify the technical and economic parameters of the reactors. Neptune is a sequence batch reactor, while MBIR is a non-mobile one. In studies performed on extracted neutron beams, these types of sources are going to complement one another”, explains Valery Shvetsov, Director of the JINR Laboratory of Neutron Physics.
“MBIR is a continuous reactor that generates enormous fluxes of fast neutrons in experimental cavities, whether they are irradiation cells or loop channels. The flows are also very prominent in horizontal experimental channels, where it is actually possible to carry out nuclear physics research, and to observe rare and super-rare nuclear processes induced by fast neutrons of the continuous spectrum. Neptune in Dubna will operate in a pulsed mode, which will make it possible to observe the same processes as on MBIR, only in the area of resolved resonances characterised by certain quantum numbers. It should be noted that both reactors will have the most intense neutron sources in the world, each in its respective grade, of course”, said Dmitry Klinov, IPPE Deputy Academic Director for prospective subject areas.
Having held two meetings, the scientists from both institutes outlined the main focus areas for MBIR and Neptune. One of them is nuclear astrophysics. “Meteorites, comets and space radiation sometimes conceal secrets, which can be revealed on Earth, with the help of neutron experiments”, D. Klinov said.
Thus, one of the most exciting projects is the assessment of the composition of Przybylski’s star in the constellation of Centaurus. Scientists suggest that it consists of superheavy elements whose lifespan on Earth would last for mere fractions of a second.
Another route is the search for new types of radioactive decay. Experimenting with neutrons on the tandem of two reactors, scientists hope to capture the predicted, but not yet proven phenomenon of pionic decay of heavy nuclei. “To witness a new natural phenomenon is important in itself, but pionic decay can lead us to the discovery and understanding of an even deeper phenomenon, that is, the existence of superdense nuclear matter on Earth”, D. Klinov noted.
“According to the idea of theoretical physicist Arkady Migdal, superdensity is related to the so-called pionic condensate. We want to detect pionic decay in very complex correlation experiments. For that, we are going to need very, very many neutrons”, the expert pointed out.
The experiments carried out on the new reactors can give answers to many questions about the origin of the Universe. “For example, generating a source of ultracold neutrons at one of MBIR channels will open up great prospects. It is this source that will make it possible to perform experimental search for neutral particle oscillations or for the electric dipole moment of the neutron, to measure the lifespan of a free neutron, etc.”, V. Shvetsov said.
Other scientific challenges that can be clarified by experiments with the reactor couple are cold nuclei multifragmentation, violation of conservation laws in nuclear reactions, nuclear data of the issues of nucleosynthesis in the Universe, nuclear drip lines, coexistence of physical forms of nuclear matter, neutron clusters, etc.
