Status Report on the Centro Nazionale di Adroterapia Oncologica (CNAO)

The Centro Nazionale di Adroterapia Oncologica (National Center for Oncological Hadrontherapy, CNAO) will be the first Italian center for deep hadrontherapy. It is presently under construction in Pavia. It will be based on an evolution of the PIMMS synchrotron capable to accelerate carbon ions up to 400 MeV/u kinetic energy and protons up to 250 MeV, energies which are necessary to treat deep seated tumors. Four treatment lines, in three treatment rooms, and a dedicated facility for clinical and radiobiological researches are foreseen in a first stage. Space for two additional rooms eventually equipped with gantries has been left aside the center and the synchrotron has been designed to work with these two additional lines, but they are intended as a future upgrade. The beam is injected into the synchrotron from the inside, to allow positioning all the injection chain inside the synchrotron ring itself, and also to better exploit the two nondispersive regions in the synchrotron. The injection chain is made by a 8 keV/u Low Energy Beam Transfer line (LEBT), a RFQ accelerating the beam to 400 keV/u, a LINAC to reach the injection energy of 7 MeV/u and a Medium Energy Beam Transfer line (MEBT) to transport the beam to the synchrotron. This report describes the design and the performances of the CNAO, and reports about the status of the construction of the center