• V. Kornilov, O. Boine-Frankenheim
  GSI, Darmstadt
• V.V. Kapin
  ITEP, Moscow

Octupole magnets can be used as a passive cure against transverse collective instabilities. The octupole field creates a betatron frequency spread due to amplitude-dependent tune shift and thus enhances Landau damping. The drawback is the reduction of the dynamic aperture (DA). Ultimately, a balance between collective damping and DA must be found. Here we analyse the transverse coherent instability thresholds in SIS100 with octupoles and nonlinear space-charge taken into account. As the major impedance sources at low frequencies, the resistive wall and the kickers are considered. A coasting beam is assumed, which results in a conservative stability estimation. On the other hand, we simulate the DA of the SIS100 lattice using the MADX code, with systematic multipole errors, random multipole errors, and closed-orbit errors taken into account.

• A.O. Sidorin, A.V. Butenko, E.D. Donets, E.E. Donets, V.V. Fimushkin, A. Govorov, V. Kobets, I.N. Meshkov, V. Monchinsky, G.V. Trubnikov
  JINR, Dubna, Moscow Region
• A. Belov
  RAS/INR, Moscow
• O.K. Belyaev, Yu.A. Budanov, A.P. Maltsev, I.A. Zvonarev
  IHEP Protvino, Protvino, Moscow Region
• V.V. Kapin
  MEPhI, Moscow

The injector complex of the NICA facility consists of existing Alvarez-type linac LU-20 and new heavy ion linac HILac. The LU-20 is under modernization now, the HILac will be constructed during coming years. Parameters of the accelerators are presented.