Possibility to investigate P-parity violation in nuclear collisions at facility NICA

Abstract

A possible experimental setup for measuring the effect of parity violation in the interaction of the polarized proton or deuteron beams with an unpolarized target is discussed. One possibility is investigation of scattering of the proton or deuteron polarized beams on a thick internal target in one of the rings of the NICA collider. In this case, the spin of a circulating particles is transformed into a mode precessing in the horizontal plane using an RF flipper. The effect of parity violation will be studied by measuring the correlation of the interaction cross section of particles and the direction of their spins. In an alternative approach, the flipper transforms the spins of particles into a horizontal plane and the beam is extracted into the channel in a certain phase of the precession.In this more traditional experimental setup, the total cross section of the passage of particles through a dense target is measured, depending on the sign of the helicity of the polarization of the beam.

Parity violation in high-energy proton-proton scattering

“…The observation of the parity-violating dependence of the total cross section on the helicity of accelerated protons is one of the actual tasks in the program of polarization experiments at the NICA collider [1][2][3]. P-odd single-spin asymmetry A = (σ + − σ − )/(σ + + σ − ) in elastic and deep inelastic scattering of longitudinally polarized electrons due to interference of weak and electromagnetic interactions has been studied both theoretically and experimentally [4][5][6][7].…”

“…The most accurate data on the P-odd asymmetry in total cross sections were obtained for the scattering of longitudinally polarized protons and neutrons with energies of tens of MeV and below, usually described by P-odd meson exchange potentials. The question on the asymmetry of A at high energies remains open [1]. Assuming experiments at the NICA collider, here we discuss energies in the center-of-mass frame, much smaller than the masses of the W and Z bosons, when the microscopic weak interaction Hamiltonian can be considered as a contact current-current one.…”