Quantized vortices in pionic superfluid
1 Joint Institute for Nuclear Research, 141980, Dubna, Russia
2 Institute of Theoretical and Experimental Physics, NRC Kurchatov Institute, B. Cheremushkinskaya 25, Moscow 117218, Russia
3 Dubna State University, 141980, Dubna, Russia
4 Pacific Quantum Center, Far Eastern Federal University, 10 Ajax Bay, Russky Island, Vladivostok 690950, Russia
Published online: 11 January 2022
The interplay between classical vorticity being the main undisputed source of polarization in heavy-ion collisions (HIC) and quantized vortices is considered. The vortex tubes emerging in the rotating pionic (super) fluid polarize the baryons in their cores and explain the emerging global polarization. The appearance of vortices in the region separating participants and spectators in non-central HIC is similar to that for sliding layers of liquid helium. From the other side, it is also the region where the classical vorticity was earlier found to be large forming the vortex sheets. The formation of tubes manifests a threshold at certain critical vorticity implying the vanishing polarization at lower energies. For central HIC the compact jet-like flows may lead to formation of vortex rings related to local polarization. The P-odd momentum correlations for their experimental investigation are suggested. The role of shear and viscosity in the emergence of polarization is discussed.
© The Authors, published by EDP Sciences, 2022
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