LATTICE DESIGN FOR 5 MeV-125 mA CW RFQ OPERATION IN THE LIPAc

The installation and commissioning of the LIPAc are ongoing under the Broader Approach agreement, which is the prototype accelerator of the IFMIF for proof of principle and design. The deuteron beam will be accelerated by the RFQ linac from 100 keV to 5 MeV during the commissioning phase-B and by the SRF linac up to 9 MeV during the phase-C. The commissioning phase-B+ will be implemented between phase-B and C to complete the engineering validation of the RFQ linac before installing the SRF linac. The lattice for the deuteron beam of 5 MeV and 125 mA at the commissioning phase-B+ was designed. INTRODUCTION The International Fusion Materials Irradiation Facility (IFMIF) aims to provide an accelerator-based, D-Li neutron source to produce high energy neutrons for DEMO reactor materials qualification. The Linear IFMIF Prototype Accelerator (LIPAc) is the prototype accelerator of the IFMIF for proof of principle and design. The installation and commissioning of the LIPAc are ongoing under the Broader Approach agreement, concluded between the European Atomic Energy Community (Euratom), whose implementing agency is F4E, and Japan [1, 2]. Figure 1: Accelerator components at (a) commissioning phase-B, (b) phase-B+, and (c) phase-C and D. At the LIPAc, the deuteron beam (D+) of 140 mA generated from the injector will be accelerated by the RFQ linac from 100 keV to 5 MeV. During the commissioning phase B, the D+ will be transported through the medium beam transport system (MEBT) and the beam diagnostic system (D-plate), and then it will be absorbed by the low power beam dump (LPBD) (see Fig.1(a)). It should be noted that, at the MEBT, there are 2 scrapers to remove the halo and 2 bunchers to match the longitudinal beam distribution to the SRF’s one (see Fig. 2). Figure 2: Schematic view of LIPAc at phase-B+. The commissioning phase-B+ will be implemented between phase-B and C. Its main goal is to validate the CW operation of the RFQ linac on the condition of the D+ with 125 mA and 5 MeV for 30 minutes before installing the SRF linac. The phase-B+ consists of substituting the SRF linac in the phase-C configuration for a new beam transport line, which is called the drift line (see Figs. 1(b) and (c)). After passing through the drift line and the high energy beam transport system (HEBT) merged with the D-plate, the D+ will be absorbed by a high power beam dump (HPBD). During the phase-C, the D+ will additionally be accelerated by the SRF linac up to 9 MeV. The CW operation is not foreseen in phase-C, and it is foreseen in the phase-D whose accelerator components is identical with those of the phase-C. In the new drift line at the Phase-B+, 4 quadrupole magnets, 2 steering magnets and 2 BPMs are assembled (Fig. 2). In order to meet the beam requirements for the phaseB+, the lattice design was performed. The beam requirements and results are presented in detail. REQUIREMENTS FOR PHASE-B+ The requirements for the phase-B+ are listed as follows: • The installation of the SRF linac is planned after the phase-B+, so that the installation and un-installation of the drift line must be simple. Therefore, it is planned that 4 quadrupole magnets are installed as the ____________________________________________ †shimosaki.yoshito@qst.go.jp 10th Int. Particle Accelerator Conf. IPAC2019, Melbourne, Australia JACoW Publishing ISBN: 978-3-95450-208-0 doi:10.18429/JACoW-IPAC2019-MOPTS051 MC4: Hadron Accelerators A08 Linear Accelerators MOPTS051 977 Co nt en tf ro m th is w or k m ay be us ed un de rt he te rm so ft he CC BY 3. 0 lic en ce (© 20 19 ). A ny di str ib ut io n of th is w or k m us tm ai nt ai n at tri bu tio n to th e au th or (s ), tit le of th e w or k, pu bl ish er ,a nd D O I