Accelerator Physics
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Accelerator Physics

Time reversal and parity properties of pd total cross section
70th anniversary of JINR
DOI: 10.54546/NaturalSciRev.200802

Fresh look at polarized deuterons at the Nuclotron/NICA & HIAF and beyond

Being a spin-1 particle, the deuteron, when polarized, offers access to a wide range of interesting tensor observables. A quest for tensor asymmetries is at the heart of the spin physics with polarized deuterons at future colliders, and calls for frequent tensor polarization flips in storage rings or in deuterium targets. Here we focus on the JEDI developed technique of the Fourier analysis of the horizontal polarization oscillations under continuous radiofrequency-driven spin flips. The generated in this way time-stamped oscillating helicity of stored particles paves the way to the nucleon/nucleus spin structure studies and to the search for the parity violation. Simultaneously, a whole set of tensor spin asymmetries, including the off-diagonal ones needed for searches for the T-violation beyond the Standard Model, will be produced. A crucial ingredient is a long polarization lifetime, and we report the first analytic treatment of decoherence of the tensor polarization under continuous radiofrequency spin flips. Our principal conclusion is that at low- and intermediate-energy accelerators the deuteron polarization lifetime could be in the ballpark of several hours, making the oscillating polarization approach viable at the Nuclotron/NICA and HIAF. We comment on a utility of the flattop spin-tensor dichroism via oscillations in the cross section of interaction of deuterons in the internal target as a monitor of the tensor polarization. Simultaneously, the dichroism effect can be used for measuring the spin precession frequences and as a comagnetometer to synchronize spin phases of colliding bunches in a collider. Corrected: 11 August 2026 (Eq. (28) was revised; typos and grammar were corrected)
B. Gou, V. P. Ladygin, N. N. Nikolaev, F. Rathmann, A. J. Silenko, Yu. N. Uzikov
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Physics 70th anniversary of JINR
DOI: 10.54546/NaturalSciRev.200608

Synchrophasotron and Nuclotron Equipment for Investigation of Polarization Phenomena

The development of the unique cryogenic source of polarized deuterons, POLARIS, in the late 1970s was very fruitful and significantly enhanced JINR’s instrumental base for studies of nucleon-nucleon interactions as well as interactions of lightest nuclei with heavier nuclei. Experimental data on polarization-dependent effects, obtained at the Synchrophasotron and the Nuclotron, significantly influenced the worldwide understanding of strong interactions between hadrons as well as the structure of lightest nuclei (the deuteron, first of all) at short inter-nucleon distances. Experiments with polarized deuteron, proton and neutron beams at intermediate (several GeV) energies resulted in creation of wide collaborations between VBLHEP of JINR and other world centers (in the USSR and Russia, France, the USA, Germany, Japan, China). Many new and unexpected experimental results were obtained by those collaborations. In particular, many new unique results were obtained for the nucleon electromagnetic formfactors of nucleons, thanks to results of works within the ALPOM/ALPOM2 project. In addition, new ways became opened for experimental investigations with polarized 3 He beams. In this direction, new unique results were obtained. The necessary developments of the techniques for the spin program at the Nuclotron/NICA are discussed in the paper.
V. Fimushkin, N. Piskunov, E. Strokovsky, V. Ladygin, Yu. Filatov, E. Syresin