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Systems of beam injection from the Booster and fast beam extraction for injection into the collider will be developed in order for the Nuclotron to operate in the framework of the NICA accelerator complex. All systems are based on the Lambertson magnets. The shortened superconducting loop is used for compensating scattered fields in the circulating beam chamber. The finite weld resistance (on an order of several nΩ) results in gradual current storage in the loop, which influences the beam upon injection. To eliminate this effect, a heater for converting the loop into the normal conducting state in the pause between cycles is applied.

This paper presents the results of a calculation of 197Au32+ ion beam losses as they interact with atoms and molecules of residual gas in the acceleration chamber of the booster vacuum system of the NICA accelerator complex [1].

The superconducting synchrotron Nuclotron was put into operation in March 1993 at the Laboratory of High Energies, JINR in Dubna. The Nuclotron Control System (NCS) provided an efficient support for machine operation during all runs. The dedicated NCS subsystem for beam diagnostics in the injection transfer line and the Nuclotron ring is described.

The system for the single-turn injection of 5 MeV/u heavy ions into the Nuclotron is described. The system comprises a superconducting septum-magnet, kick electric plates, beam diagnostic apparatus and magnet correctors. The septum magnet has an iron yoke. The coil and septum made of a hollow superconductor, are cooled with a two-phase helium flow. The magnetic field is 1 T. The electric field and its fall time in the fast kicker are 7 kV/cm and about 100 nsec, respectively. The beam diagnostics are composed of the Faraday cups and multi-wire collector chambers for current and profile measurements over a wide range of intensities. The magnetic correctors in the beam line and the Nuclotron ring are used for injection adjustment. The system has operated since 1992. The experimental results are presented.

The superconducting synchrotron, named the Nuclotron is based on miniature iron-shaped held SC-magnets. It was put into operation in March 1993 at the Laboratory of High Energies of the Joint Institute for Nuclear Research in Dubna. Eleven runs of the new accelerator have been performed by the present time. The Nuclotron Control System (NCS) project, which is still under development, started in 1992 and has provided an efficient support for the machine commissioning through all its phases. This paper presents the current status of the whole system and some details of cryogenics, beam injection, and main power supplies subsystems.

To obtain a beam of polarized deuterons, a cryogenic source "Polaris" has been developed according to the program of. research at the Dubna synchrophasotron '''. The source is installed on a high-voltage terminal of the linac preaccelerator, A beam of deuterons from the source is accelerated in the synchrophasotron'^/. At present the source is being improved. A polarimeter with ^He and He targets has been developed to measure the polarization of the beam of deuterons after the lihac. Results of this work are presented in the report. 1. DESIGN OF THE SOURCE A cryogenic pulsed source "Polaris" for a beam of polarized deuterons is described in the Proceedings of previous symposia''''. The design of the source has been changed and improved. A principal diagram of the source is shown in Fig.l. Recently the problem of increasing the intensity of sources due to cooling an atomic beam to cryogenic temperatures has been of interest'3>^i This possibility can be easily realized in a cryogenic source. Earlier a dissociator and a nozzle of the source "Polaris" were cooled to a temperature of ~120 K as they were attached to a shield colled with liquid nitrogen. Presently, after the dissociator the atomic flow is supplied to a 4 3 mm teflon pipe 95 mm long, the end of which has a temperature of 12-38 K at the output depending on the state of contact with a liqued helium cryostat (Fig.l)'^/. Due to decreasing the temperature of the atomic beam, the aperture and length of pole tips of a superconducting sextupole magnet is changed. The configuration of several versions of the system, their geometrical dimensions, values of ion current Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/jphyscol:1985289

According to the program of research in the field of relativistic nuclear physics, a cryogenic source of polarized deuterons POLARIS has been tested at the Dubna synchrophasotron. The aim of the tests is to match the source with linac and to accelerate a beam of deuterons. The set-up is described, and results of its operation along with the accelerator are presented. 3 references, 4 figures.