THE MISALIGNMENT AND RF ERROR ANALYSESFOR THE RIA DRIVER LINAC

The proposed Rare Isotope Accelerator (RIA) [1] driver linac being studied at the National Superconducting Cyclotron Laboratory (NSCL) consists of three parts separated by two charge-stripping chicanes. Superconducting quarter-wave, half-wave and 6-cell elliptical cavities with rf frequencies ranging from 80.5 MHz to 805 MHz are proposed to accelerate light and heavy ions to final beam energies of ≥400 MeV/nucleon. Superconducting solenoids and room temperature quadrupoles are proposed to provide transverse focusing and beam matching. Because of the high final beam power (100 to 400 kW) specified for RIA operation, beam loss must be limited to avoid radiation damage. Misalignment and rf error analysis for the superconducting cavities and focusing elements in the RIA driver linac were performed, and correction schemes developed using the computer codes DIMAD and LANA. The simulation results are presented, and the misalignment and rf error specifications are given for the RIA driver Linac.