• 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.

• A.O. Sidorin, N.N. Agapov, A.V. Eliseev, V. Karpinsky, H.G. Khodzhibagiyan, A.D. Kovalenko, G.L. Kuznetsov, I.N. Meshkov, V.A. Mikhaylov, V. Monchinsky, A.V. Smirnov, G.V. Trubnikov, B. Vasilishin
  JINR, Dubna, Moscow Region
• A.V. Butenko
  JINR/LHE, Moscow

The main goal of the Nuclotron booster construction are following: accumulation up to 4·10⁺⁹ Au³²⁺ ions; acceleration of the ions up to energy of 600 MeV/u that is sufficient for stripping of the ions to the bare nucleus state; simplification of the requirements to the vacuum conditions in the Nuclotron; forming of the required beam emittance at the energy of 100 MeV/u with electron cooling system. The features of this booster, the requirement to the main synchrotron systems and their parameters are presented.

• V. Guidi, E. Bagli, A. Mazzolari
  INFN-Ferrara, Ferrara
• A.G. Afonin, Y.A. Chesnokov, V.A. Maisheev, I.A. Yazynin
  IHEP Protvino, Protvino, Moscow Region
• S. Baricordi, P. Dalpiaz, M. Fiorini, D. Vincenzi
  UNIFE, Ferrara
• D. Bolognini, S. Hasan, M. Prest
  Università dell'Insubria & INFN Milano Bicocca, Como
• G. Della Mea, R. Milan
  INFN/LNL, Legnaro (PD)
• A.S. Denisov, Yu.A. Gavrikov, Yu.M. Ivanov, L.P. Lapina, L.G. Malyarenko, V. Skorobogatov, V.M. Suvorov, S.A. Vavilov
  PNPI, Gatchina, Leningrad District
• S. Golovatyuk, A.D. Kovalenko, A.M. Taratin
  JINR, Dubna, Moscow Region
• A. Mattera
  INFN MIB, MILANO
• W. Scandale
  CERN, Geneva
• S. Shiraishi
  Enrico Fermi Institute, University of Chicago, Chicago, Illinois
• E. Vallazza
  INFN-Trieste, Trieste
• A. V. Vomiero
  INFM-CNR, Istituto Nazionale di Fisica della Materia - Consiglio Nazionale delle Ricerche, Brescia

New results in coherent interaction of negatively-charged particles with bent crystals showed unprecedentedly and significantly high efficiency to manipulate such beams, in the same way as for positively charged particles. Key feature under experimental attainment was the usage of high-quality suitably thin silicon crystals. We experimentally tested crystals Vs. 150 GeV negative pions at external lines of CERN SPS. We observed planar channeling at full deflection angle 30% high single-pass efficiency and large acceptance (about 20μrad). Moreover in the axial case, we reached more than 90% deflection efficiency and larger acceptance (about 60μrad). We also observed volume reflection in a bent crystal, at more than 70% single-pass efficiency with such a wide acceptance as the bending angle. At last, volume reflection by several planes in a single bent crystal was successfully tested with very high efficiency (about 80%). In summary both channeling and volume reflection modes appear to be useful technique for the manipulation of negatively charged beams, e.g. for collimation in the new generation of high intensity accelerators.

The UA9 collaboration

• A.O. Sidorin, I.N. Meshkov, G.V. Trubnikov
  JINR, Dubna, Moscow Region
• A.D. Kovalenko
  JINR/LHE, Moscow

The Nuclotron-based Ion Collider fAcility (NICA) is the new accelerator complex being constructed at JINR aimed to provide collider experiments with heavy ions up to uranium at the center of mass energy from 4 to 11 GeV/u. It includes 6 Mev/u linac, 600 MeV/u booster, upgraded SC synchrotron Nuclotron and collider consisting of two SC rings, which provide average luminosity of the level of 10²⁷cm^-2s^-1.

• A.O. Sidorin, N.N. Agapov, V. Batin, A.V. Butenko, D.E. Donets, A.V. Eliseev, A. Govorov, V. Karpinsky, V.D. Kekelidze, H.G. Khodzhibagiyan, A. Kirichenko, O.S. Kozlov, I.N. Meshkov, V.A. Mikhaylov, V. Monchinsky, S. Romanov, V. Shevtsov, A.N. Sissakian, I. Slepnev, V. Slepnev, G.V. Trubnikov, B. Vasilishin, V. Volkov
  JINR, Dubna, Moscow Region
• V. Alexandrov
  BINP SB RAS, Protvino, Moscow Region
• O.I. Brovko, A.D. Kovalenko
  JINR/LHE, Moscow

The 'Nuclotron-M' project started in 2007 is considered as the key point of the first stage of the NICA/MPD project. General goal of the 'Nuclotron-M' project is to prepare all the systems of the Nuclotron for its long and reliable operation as a part of the NICA collider injection chain. Additionally the project realization will increase the Nuclotron ability for realization of its current experimental program. Results of the last runs of the Nuclotron operation are presented.