Conditioning of the frontline cavities of the MYRRHA injector

The MYRRHA Project (Multi-purpose hYbrid Research Reactor for High-tech Applications) in Mol, Belgium, is an upcoming accelerator driven system (ADS) for the transmutation of long-living radioactive waste. In the injector section of the accelerator, consisting of a 4-rod RFQ and a normal conducting CH-cavity section, the protons will be accelerated up to 17 MeV before entering the superconducting gap-spoke cavity section with an output energy of 600 MeV [1].
A shortened test-injector with an output energy of 5.9 MeV is currently being installed at the SCK CEN in Louvein-la-Neuve, Belgium. This test-injector serves the purpose of testing the reliability of the planned injector [2]. When commissioning a cavity, it first has to be fed very little power to avoid damage to the structure by flashovers, discharges and multipacting. The power is then slowly increased up to full operation level. In this process, the surfaces are cleaned by heating/outgasing so that the effects disturbing operation described above do no longer occur. This paper will report on the status of the conditioning of the 176.1 MHz 4-rod RFQ up to 120 kW of the MYRRHA-injector and additional measurements concerning the gap voltage which are currently being performed at the SCK CEN.