DEVELOPMENT OF THE BEAM POSITION MONITORS SYSTEM FOR THE LINAC OF SPIRAL2

The SPIRAL 2 facility will deliver stable heavy ion and deuteron beams at very high intensity, producing and accelerating light and heavy rare ion beams. The driver will accelerate between 0.15mA and 5 mA deuteron beam up to 20 MeV/u and q/A=1/3 heavy ions up to 14.5 MeV/u. It is being built on the site of the Grand Accelerator National d’Ions Lourds at CAEN (France). The accurate tuning of the Linac is essential for the operation of SPIRAL2 and requires from the Beam Position Monitor (BPM) system the measurements of the beam transverse position, the phase of the beam with respect to the radiofrequency voltage and the beam energy. This paper addresses the advancement made during the last twelve months on the realization of the 22 BPM required for the SPIRAL 2 Linac. The BPM sensors are now completed and tested. The design of the acquisition card for the BPM of the SPIRAL2 Linac is given and will be described. The prototype card is realized and under test. The first results are given. The aim is to verify the main parameters: sensitivity, position and phase measurement, and the appropriate behavior of the BPM acquisition card in all cases (pulsed, electrode signal reconstruction, interlock, post mortem).