Numerical calculation of ion polarization in the NICA collider

Numerical modeling of a proton spin-flipping system in the spin transparency mode at an integer spin resonance in JINR's Nuclotron

“…There is an opportunity to not only stabilize the polarization but to also manipulate its direction at the imperfection resonance points using additional fields. Spin navigators can be technically realized in different ways using longitudinal and transverse fields [6,7]. At the 𝛾𝐺 = 2 resonance in Nuclotron, it is most efficient to use weak solenoids, which have no effect on the closed orbit.…”

“…In this case, small perturbing fields due to construction and alignment errors of 2021 JINST 16 P12039 the lattice magnetic elements as well as due to betatron and synchrotron oscillations rotate the spin about an a-priori unknown direction. The spin direction in the ST mode can be stabilized by a "spin navigator", a compact insertion including weak solenoids, rotating the spins by small angles [6,7].…”

Acceleration of polarized protons and deuterons in the ion collider ring of JLEIC

“…any orientation of the particle spin at any orbital location repeats from turn to turn. To preserve the polarizations of the proton and deuteron beams during acceleration from 8 GeV/c to 100 GeV/c in the ion collider ring, it is sufficient to use a weak solenoid with a field integral of 1.2 Tm, which does not perturb the design orbit and has practically no effect on the beam's orbital parameters [3][4][5][6][7][8][9][10]. The solenoid then stabilizes longitudinal spin polarization at its location.…”

“…It describes the effect of the ring as a whole on the spin due to a -function-like radial field [8]. Another option is to compensate the coherent part of the spin resonance strength at the experimental energy using a 3D spin rotator [4][5][6][7][8]10]. Similar graphs for the longitudinal components of the deuteron spin are shown in Figure 7.…”