How to monitor the beam loss in SPIRAL2 linear accelerator
F. Negoita et al.
All high intensity accelerators around the world are equipped with beam loss monitors (BLM). In general, the BLM systems aim to:
- Protect accelerator components
- Diminish activation
- Help tuning/optimizing the beam
To this goal, a BLM must provide continuously measured values of intensities and positions of beam losses as well as a fast “Beam Stop” signal when allowed limits of beam loss are exceeded.
The proposed BLM system for SPIRAL2 consists of a number of plastic scintillators coupled to photomultipliers followed by discriminators. A collaboration led by IFIN-HH, Romania, has realized different prototypes of BLM detectors within the European Project SPIRAL2 Preparatory Phase. The prototypes were tested with gamma sources and ion beams at the tandem accelerator of IFIN-HH using as targets samples of materials to be used in linac construction. The tests have been completed with simulations to take into account the efficiencies of detectors and the neutron and gamma fluxes created in the detectors.
Several tests are planned in the next future: X-rays background, radiation hardness tests, beam loss measurements at SARAF accelerator (Israel) correlated to beam halo measurements. More detailed simulations are also required, in order to estimate absorption and scattering of emitted neutrons and gammas, as well as the usefulness of local shielding/collimation of detectors.