Beam commissioning in the first superconducting segment of the Facility for Rare Isotope Beams

Linac segment 1 (LS1) of the FRIB driver linac is composed of 15 cryomodules, consisting of 104 superconducting (SC) resonators and 39 SC solenoids. Four ion beam species (Ne, Ar, Kr, and Xe) were successfully accelerated up to 20.3 MeV/u in LS1 and transported to the designated beam dumps located in folding segment 1 (FS1). 100% beam transmission was measured through all cryomodules and the warm section of LS1. High-power equivalent beams were delivered to the beam dump in two modes: pulsed and continuous wave (cw). In the pulsed mode, the peak intensity of the argon beam was 14.8 p mu A at 3% duty factor, which constitutes 30% of the FRIB design intensity for this particular ion beam. A cw argon beam was accelerated, demonstrating that the FRIB linac in its current configuration is the highest-energy cw superconducting hadron linac in the world. This paper presents a detailed study of beam dynamics in LS1 prior to and after charge stripping with a carbon foil.