The Design of a Proton-Heavy Ion Hybrid Synchrotron Upgraded from XiPAF Proton Ring

Xi’an 200MeV Proton Application Facility (XiPAF) has been basically completed at the end of 2020, providing proton beams of 10 to 200 MeV for space radiation effect studies on electronics. To expand its capabilities, XiPAF is undergoing an upgrade to deliver multiple ion species, from proton to Bismuth ion. The upgrade focuses on three aspects. First, the original negative hydrogen linear injector will be remodeled to a proton linear injector. Second, a heavy ion linear injector will be added. Third, the existing proton ring will be retrofitted into a hybrid proton-heavy ion synchrotron. Correspondingly, the beam transport lines will also be modified. This paper details the considerations and physical designs for upgrading the synchrotron. Within the scope, we discuss the challenges and solutions in transforming a specialized proton synchrotron into a multi-ion accelerator under the constraints of existing plant layout and reuse of existing equipment.