Vacuum Conditions and the Lifetime of a Single-Charged Helium Ion Beam in the Booster Synchrotron of the NICA (First Run)

JETP Letters - The results of the first run (December 2020) for the commissioning of the new superconducting synchrotron Booster at the Joint Institute for Nuclear Research are presented. Vacuum...     

Progress in development of Nuclotron accelerator complex

The Nuclotron superconducting synchrotron was constructed in 1987–1992 [1]; it is the world’s first synchrotron based on fast cycling “window frame” electromagnets with a superconducting coil. For a design field of dipole magnets of 2 T, the magnetic rigidity is 45 T m, which corresponds to the energy of heavy nuclei (for example, gold) of 4.5 GeV/nucleon. The Nuclotron accelerator complex is currently being upgraded (the Nuclotron-M project); this upgrade is considered a key part of the first stage of fulfilling the new Joint Institute for Nuclear Research (JINR) project: the Nuclotron-based Ion Collider fAcility and Multi-Purpose Detector (NICA/MPD). The most important task of this new project is the preparation of basic Nuclotron systems for its reliable operation as part of the NICA accelerator complex. Basic results of activity on the project, which started in 2007, are presented and the results of the last Nuclotron runs are analyzed.     

Testing prototypes of high-temperature superconducting current leads of cryogenic stand for testing magnetic elements of the NICA accelerating complex

In the Laboratory of High Energies at the Joint Institute for Nuclear Research, as part of the NICA-MPD [1] project, tests of two prototypes of HTSC current leads prepared at ASIPP institute (Hefei, China) have been performed [2, 3] to measure electric and heat parameters and to search for structural and physical drawbacks. Based on the experimental results, necessary changes are made in the structure of HTSC current leads of the testing stand for the magnetic element testing of the NICA accelerating complex and its basic setups: the Nuclotron, Booster, and Collider.     

Results of the Nuclotron-M project

The main goal of the Nuclotron-M project, approved in 2007, was formulated as follows: modernization of the main accelerator systems for reliable and safe operation of the Nuclotron as a part of the accelerator facility NICA (Nuclotron-based Ion Collider Facility) being constructed at JINR. Demonstration of heavy-ion beam acceleration (with atomic mass number higher than 100) as well as safe and stable operation of the main superconducting system operation at a magnetic field of up to 2 T had been defined as criteria of successful project fulfillment. Another very important issue is performance of stable, long-term beam runs and increase of the accelerated beam intensity. All the main goals of the Nuclotron-M project had been successfully achieved by the end of 2010. In this report we give an overview of the project realization chronology and present the main experimental results obtained at LHEP Nuclotron accelerator facility in the period from 2007 to early 2011.     

The State of the Magnetic Measurements of the NICA Collider Twin-Aperture Dipoles

Physics of Particles and Nuclei Letters - The lattice of the NICA collider includes 80 twin-aperture superconducting dipole magnets. Measurements of the magnetic field parameters should be done for...     

Correctors’ Magnets for the NICA Booster and Collider

Physics of Particles and Nuclei Letters - The NICA accelerator complex will consist of two injector chains, a new 600 MeV/u superconducting booster synchrotron, the existing superconducting...     

Booster synchrotron of NICA accelerator complex

NICA is a new accelerator complex being constructed at the Joint Institute for Nuclear Research; the main task of this complex is to perform collider experiments for ion beams up to uranium with energies of up to 3.5 × 3.5 GeV/nucleon. This complex includes an electron string ion source, a 6 MeV/nucleon linear accelerator, a booster, the Nuclotron, and a collider with an average luminosity of 10²⁷ cm² s^?1. The main tasks of the booster are to accumulate up to 4 × 10^{9 197}Au³²⁺ ions, to accelerate to 600 MeV/nucleon (sufficient enough energy for completely stripping nuclei), to reduce the requirements of vacuum conditions for the Nuclotron, and to form the necessary beam emittance using an electron cooling system. The specific features of the NICA booster and the requirements for the basic systems of the synchrotron and their parameters are presented in this paper.     

Measurement of the magnetic-field parameters of the NICA Booster dipole magnet

Serial assembly and tests of dipole and quadrupole magnets of the NICA Booster have started at the Laboratory of High Energy Physics of the Joint Institute for Nuclear Research (JINR). The accelerator is fitted with Nuclotron-type magnets with a superconducting winding and an iron yoke for shaping the needed magnetic field. The design of magnets for NICA was optimized (based on the experience gained in constructing and operating the JINR Nuclotron) for the production of magnetic fields of the required configuration in terms of the beam dynamics in the accelerator and the collider. Measurements of parameters of the field of each magnet are expected to be performed in the process of assembly and testing of each module of the magnet-cryostat system of the NICA Booster and Collider. The results of magnetic measurements for the NICA Booster dipole magnet are presented.     

Optical Structure and Dynamic Aperture of the NICA Сollider

The optimized optical structure of the NICA collider is considered. Studies and calculation methods of the stability region of the motion of charged particles in the collider—the dynamic aperture—are presented. The influence of the magnetic-field nonlinearities, in particular, the fringe fields of the magnetic elements on the dynamic aperture, is considered. The dependences of the dynamic aperture on optical properties of the collider, the choice of the working point of betatron frequencies, and tuning parameters of the beam-interaction region are shown. The methods for compensating the effect of the fringe fields on the stability of beam dynamics are discussed.