The vacuum tests of the first segment of the ESS Bilbao RFQ have been successfully completed. The RFQ is a linear accelerator that serves as a bridge between high-voltage of the ion source and the Accelerator cavities named DTL. It is a key component since it accelerates protons from 45keV to 3MeV keeping the beam focused. The peculiarity of the ESS Bilbao RFQ, consisting of 4 segments with a total length of about 3 meters, is that the vanes that form each of the segments are assembled with polymeric vacuum gaskets and are not conventionally welded by brazing. This innovative assembly system technology has been previously used in the RFQ manufacturing process of the RAL-ISIS neutron source and reference center in the field.
This system has the main advantage that if the assembly is not perfect in its alignment, it can be disassembled and reassembled without prejudice to the manufacturing process, while if it was welded by brazing there is no option to assemble and disassemble the system. The disadvantage, on the other hand, is that it is not 100% guaranteed that the vacuum levels required to operate an accelerator are achieved. For this reason, it was decided to manufacture a first segment in which to test this technology that has recently been validated thanks to the good results of the vacuum tests carried out at the ESS Bilbao facilities.
The steps to develop until the complete manufacture of the RFQ is achieved, are the RF tests at low power and with water temperature. If these tests that are planned to be carried out in January are positive, both the manufacturing and the technology of our RFQ will be validated and the rest of the component segments will be tendered.