D-polarized ion source POLARIS for the JINR accelerator Nuclotron

The spin physics program is an important part of the LHe JINR scientific program. An intensive study of polarization phenomena was carried out at the Dubna 4.5 GeV/nucleon synchrophasotron, using cryogenic source of polarized deuterons ( ↑ D + ) POLARIS and several polarimeters. After commissioning of the new superconducting accelerator Nuclotron, it is planned to continue the spin physics program. There is a project to produce an intensive polarized deuteron beam in the new accelerator. At present, the Nuclotron has a short one-turn injection ( 8 μ s ) of positive ions. To increase the intensity of the accelerated polarized beam up to 0.7– 1.0 × 10 10 ↑ d / pulse the source POLARIS is reconstructed into a ↑ D - source and a multiturn (20–30 turns) charge exchange injection of negative ions will be applied. Simulation shows that there are no depolarizing resonances during acceleration of polarized deuterons almost at all energy ranges of the machine. A test run at the Nuclotron has been done using the existing ↑ D + source POLARIS to check the polarization of low- and high-energy beams. A high degree of vector polarization of the deuteron beam behind the 10 MeV linac, inside the accelerator ring and after the beam extraction is confirmed. The source design, setup parameters and results of the polarization measurements are presented.