Commissioning Results of the TOP-IMPLART 27 MeV Proton Linear Accelerator

The results of a 27MeV proton LINAC commissioning are presented. The linac, operating at ENEA Frascati Research Center, consists of a 425MHz injector followed by a 3GHz booster. The injector is a commercial LINAC (ACCSYS-HITACHI PL7) composed by a duoplasmatron source with einzel lens, a 3MeV RFQ and a 7MeV DTL. Wide injection current range (0-1.5mA) is obtained varying extraction and lens potentials. The booster is a sequence of 3 SCDTL (Side Coupled DTL) modules with output energies of 11.6, 18 and 27MeV. Each module requires less than 2MW peak power in 4us length pulses. All modules are powered by a single klystron. The output beam has been characterized at 10Hz PRF. Fast AC transformers, Faraday cup and ionization chamber have been used for current/charge monitoring, while energy has been measured using a novel detector based on LiF crystals. Systematic measurements have been done to investigate the sensitivity of output beam to machine operating parameters (SCDTL temperatures, stability of injector and RF power) highlightning the existing correlations. The LINAC is part of a 150MeV protontherapy accelerator under development in the framework of the TOP-IMPLART Project.