Developments at the CERN-ISOLDE Offline 2 mass separator

The Offline 2 mass separator laboratory is part of the CERN-ISOLDE Offline facilities - a suite of installations required to perform essential quality control on target and ion source units before irradiation at CERN-ISOLDE (Catherall et al., 2017) [1]. The facility is also used for extended preparatory offline studies as a prerequisite before conducting any beam development on-line, especially establishing systematic effects. The Offline 2 separator resembles the on-line CERN-ISOLDE Frontend and employs identical services such as beam instrumentation, gas delivery system, laser ionization and the equipment control system. The facility is able to generate dc as well as bunched non-radioactive beams up to an energy of 60keV. The mass resolving power of the existing 90° dipole mass separator magnet is R≈500 (Warren et al., 2020) [2]. The ion beams can be cooled and bunched in an unmodulated RFQ. In order to study effects of the RFQ buffer gas on the formation of molecular species, a dedicated identification setup is required. We intend to employ a Wien filter downstream the RFQ. This work presents initial beam dynamics simulations through the entire Offline 2 facility to prepare injection into the RFQ. The fields of the RFQ are also shown serving as a basis for field map PIC simulations. Furthermore, we present the status of the emittance meter preparations in front of the separator magnet allowing a comparison to the beam dynamics simulations.