Consorzio RFX, Associazione Euratom-ENEA sulla Fusione, Padova
INFN/LNL, Legnaro, Padova
CERN, Geneva
The Legnaro National Laboratory (LNL) is building the 30 mA, 5 MeV front end injector for the production of intense neutron fluxes for interdisciplinary application. This injector comprises a proton source, a low energy beam transport line (LEBT), a radio frequency quadrupole (RFQ) and a beam transport line designed to provide a 150 kW beam to the berillium target used as neutron converter. The RFQ, developed within TRASCO project for ADS application, is designed to operate cw at 352.2 MHz. The structure is made of OFE copper and is fully brazed. The RFQ is built in 6 modules, each approximately 1.2 meter long. This paper covers the mechanical fabrication, the brazing results and acceptance tests for the various modules.
CERN, Geneva
CEA, Gif-sur-Yvette
The first stage of acceleration in Linac4, the new 160 MeV CERN H- injector, is a 352 MHz, 3 m long Radiofrequency Quadrupole (RFQ) Accelerator. The RFQ will capture a 70 mA, 45 keV beam from the rf source and accelerate it to 3 MeV, an energy suitable for chopping and injecting the beam in a conventional Drift Tube Linac. Although the RFQ will be initially operated at low duty cycle (0.1%), its design is compatible with higher duty cycle (10%) as the front-end for a possible high-intensity upgrade of the CERN linac facility. The RFQ will be of the brazed-copper design and will be built and assembled at CERN. Beam dynamics design allows for a compact structure made of a single resonant unit. Field symmetry is ensured by fixed tuners placed along the structure. In this paper we present the rf and mechanical design, the beam dynamics and the sensitivity to fabrication and to rf errors.