Beam diagnostics of an ECR ion source on LIPAc injector for prototype IFMIF beam accelerator

Abstract

The IFMIF accelerator facility consists of 2 identical linacs, each accelerating a 125 mA CW deuteron beam up to the energy of 40 MeV. In order to reach these unprecedented performances, the Linear IFMIF Prototype Accelerator (LIPAc) is under installation and commissioning at the International Fusion Energy Research Centre (IFERC) in Rokkasho, Japan, in the framework of the IFMIF/EVEDA project, which is part of the Broader Approach (BA) agreement between Japan and EU. The accelerator is designed to validate components up to 125 mA CW deuteron beam at 9 MeV. The accelerator components of LIPAc have been designed and manufactured mainly by European Institutes. The injector and superconducting linac, RFQ, MEBT, Diagnostics Plate, HEBT and beam dump have been developed respectively by CEA-Saclay, INFN-Legnaro and CIEMAT-Madrid and were delivered to Rokkasho between 2013 and 2016. The commissioning of the injector with beam started in November 2014. This paper dealt with the experimental data obtained with the beam diagnostics of the injector. The electrical measurements of the beam intensity on the beam stopper were compared with calorimetric measurements. The beam profiles measured with a CCD camera and a custom image-intensified CID camera are also addressed. The analysis of beam emittance and ion species fractions from data obtained with an Allison scanner is described and the results of species fraction measurements are compared with those obtained by using a deported spectrometer. Finally, the analysis of beam space potential from data obtained with a 4-Grid analyser is presented.