Joint JINR Seminar,

04-27-2022 11:00 онлайн

After running of the program of spin experiments on the SPD detector, the NICA@JINR complex becomes a unique platform in the world, fully equipped for studying fine precision spin phenomena at energies of tens of GeV in c.m. In addition to key experiments on gluon helicity in protons and deuterons as an important contribution to addressing the mystery of the spin crisis, NICA possesses a high potential to study fundamental symmetries in spin experiments, which will be the main topic of the report.

In the following area there is already a solid reserve of Russian physicists from JINR, MIPT, INR RAS, ITP RAS, INP SB RAS. These are developments in the theory of the frozen spin mode for the search for EDM at NICA [Yu. V. Senichev et al.]; development of the oscillating polarization technique to search for spatial parity nonconservation [I. M. Sitnik, N. M. Piskunov, Yu. M. Shatunov, I. A. Koop, A. I. Milstein, N. N. Nikolaev et al.], new methods for searching for CP-nonconservation outside the Standard Model of T-noninvariant effects of spin rotation [Yu. N. Uzikov, N. N. Nikolaev], the search for axions as a promising source of dark matter in the Universe [A. Ya. Silenko, N. N. Nikolaev]. There is a wide experience in polarization experiments at VBLHEP JINR and addressing some of the above mentioned tasks requires only an insignificant development of the occurring equipment.

The task of providing a stable polarization of deuterons at the point of interaction is till central to the SPD experiments. Since addressing this task using traditional methods is difficult, a new promising spin transparency approach has been proposed at MIPT, JINR and JLab [Ya. S. Derbenev, A. D. Kovalenko, A. M. Kondratenko, M. A. Kondratenko, V. S. Morozov, Yu. N. Filatov]. Apart from SPD@NICA, this approach seems to be the only realistic one for studying the spin crisis at the eIC@BNL electron-ion collider.

Since experiments at MPD and SPD are equally essential components of the NICA@JINR physics program, we submit for discussion plans for a full test of the ideas of spin transparency at Nuclotron and NICA at JINR, as well as supplementing NICA with a bypass for implementing experiments to search for the EDM of protons and deuterons. Here, an experience of a long-term work of the members of the team on spin dynamics in storage rings within the framework of the JEDI collaboration would be useful. After returning to JINR-FAIR cooperation, it could be extended to spin physics at NICA.