The low energy beam transport line for the MYRRHA accelerator

International audienceThe MYRRHA Project aims at the construction of a new research reactor in Mol (Belgium) todemonstrate the transmutation feasibility with an accelerator-driven system (ADS). In its subcriticalconfiguration, the MYRRHA facility requires a proton flux with a maximum power of 2.4 MW(600 MeV – 4 mA). Such a continuous wave (CW) beam will be delivered by a superconducting linearaccelerator (linac) which must fulfil very stringent reliability requirements to ensure the safe ADSoperation with a high level of availability. The proton beam will be injected in the superconductinglinac with an energy of 17 MeV. The injector will enable to condition and pre-accelerate the protonbeam from 30 keV to 17 MeV. The injector is composed of: the proton source, the low-energy beamtransport line (LEBT), the Radio-frequency quadrupole (RFQ), and a series of CH-DTL cavities. Due tothe very-high reliability requirements it is absolutely necessary to carry out prototyping of all theelements of the accelerator in order to optimise its operation. In this purpose a LEBT prototype hasbeen built and is presently installed and operated at LPSC Grenoble (France). An experimentalprogramme to optimise the tuning of the line, the beam transport and to study the space-chargecompensation mechanism, is in progress. Once the line is commissioned it will be moved to Louvainla-Neuve (Belgium) to be coupled with the RFQ. We here review the construction and thecommissioning of the LEBT. Some experimental results are discussed, in particular the observedspace-charge compensation effects