Beam Diagnostics of the LIPAC Injector With a Focus on the Algorithm Developed for Emittance Data Analysis of High Background Including Species Fraction Calculation
Résumé
To prove the feasibility of the IFMIF accelerators concept, the EVEDA phase will commission in Japan the LIPAC accelerator, which will deliver a 125 mA/9 MeV CW deuteron beam. LEDA already managed 100 mA in CW at 6.7 MeV in 2000. The different subsystems of LIPAC have been designed and constructed mainly by European labs with the injector developed by CEA-Saclay. This injector must deliver a 140 mA/100 keV CW deuteron beam at 99% D⁺ ratio, which is produced by a 2.45 GHz ECR ion source. The low energy beam transport line is based on a dual solenoid focusing system to transport the beam and to match it into the RFQ. The normalized RMS target emittance at the RFQ entrance is targeted to be within 0.25π mm·mrad. This article describes the diagnostics installed in the LEBT to measure beam parameters such as intensity, profile, emittance, species fraction and degree of space charge compensation. The article also focuses on the algorithm developed to analyze emittance data of high background from an Allison scanner. Species fractions (D⁺, D2+, D3+) using mass separation technique were also calculated with the Allison scanner installed between the two solenoids in a first stage.