Natural science

Particle of four neutrons exists, but a short time

Tetraneutron. Photo: A. Shirokov

Scientists of the Moscow State University (MSU of M. Lomonosov) in the international team with German and American scientists proved the existence of tetraneutron (the particles of the four neutron) during 5×10-22 sec. This could be the beginning of the revision of our knowledge about atomic nucleus.

Neutron is neutral, i.e. uncharged elementary particle, which presents in the nuclei of chemical elements apart from hydrogen. Its neutrality allows it to penetrate into the nucleus, causing its transformation and decomposition. The life of a neutron outside the nucleus is about 15 minutes before the collapse. Scientists aimed to find out whether a system composed of neutrons like a “neutron star” exists.

The science team member – senior researcher of the Institute of nuclear physics named after D. Skobeltsyn (SINP MSU) Andrey Shirokov, explained to “E-Vesti” readers the application of scientific discoveries: “At the moment there is no technological application of the work over tetraneutron. First of all, discovering of tetraneutron should be confirmed by independent experiments of other groups, only then we can say that tetraneutron is really discovered. Next, we used a new unconventional interaction between neutrons; it is necessary to check whether tetraneutron is not communicated with more traditional interactions. If this would be confirmed, there is a revision of our knowledge about atomic nucleus, and there is potential to find application in a variety of nuclear technologies, for example, in the problem of nuclear waste disposal”.

Scientific problem of the system of the four neutron – tetraneutron existence is in the focus of scientists about 65 years. By this time the absence of systems of two and three neutrons was already proven, and in 2002 French scientists discovered the events, probably related to the formation of tetraneutrons. Then the research has involved scientists from different countries.

Russian scientists from Moscow state University took part in the work upon the invitation of the German colleagues. Our scientists had made work on not previously held theoretical estimates of the energy of the resonant state tetraneutron and its lifetime at low energies of about 1 MeV. They applied the new theoretical approach to the study of resonant States in nuclear systems, which are today.

Replying our question whether we should work in international teams, Andrey Shirokov answered affirmatively: «This is extremely important, not only in our area. Here we exchange ideas, and we have access to supercomputers much more productive than we have here in our country».

“Our main work is held as a part of the teams. These are always open projects with a focus on supercomputer modelling of the properties of atomic nucleus. We examine a wide range of atomic nucleus, including exotic nuclear systems consisting of only a few neutrons”, – explained the direction of his research for “E-Vesti” A. M. Shirokov.