• A.D. Kovalenko, N.N. Agapov, V.D. Kekelidze, H.G. Khodzhibagiyan, I.N. Meshkov, V.A. Mikhaylov, V.A. Petrov, A.N. Sissakian, A. Sorin, G.V. Trubnikov
  JINR, Dubna, Moscow Region

NICA (Nuclotron-based Ion Collider fAcility) is the new accelerator complex currently under construction at JINR. The facility is aimed to provide collider experiments with heavy ions up to uranium (gold at the beginning stage) with a centre of mass energy up to 11 GeV/u and an average luminosity up to 10²⁷ cm^-2 s^-1. The collisions of polarized deuterons and protons are foreseen also. The accelerator complex includes two injector linacs, a superconducting booster synchrotron, a 6 GeV/u superconducting synchrotron (existing Nuclotron) and a collider consisting of two storage rings. Different modifications of superferric magnets based on a hollow composite NbTi cable operating at 4.5 K is proposed to be used for the NICA booster and collider rings. The twin-aperture collider dipole consists of two vertically assembled cold masses placed inside a common thermal shield and a common cryostat. The dipole good field aperture is fixed to 60 mm. The 2 T option, which design is very similar to the Nuclotron's one, was fixed as basis for the collider of 350 m long. R&D work on a curved 4 T Cosine(θ)-dipoles based on a hollow Nuclotron-type cable is proposed to be continued.