Performances of the scanning system for the CNAO center of oncological hadron therapy

Abstract

Abstract. In hadron-therapy one of the most advanced methods for beam delivery is the active scanning technique which uses 37 fast scanning magnets to drive a narrow particle beam across the target. The Centro Nazionale di Adroterapia Oncologica 38(CNAO) will treat tumours with this technique. The CNAO scanning system includes two identical dipole magnets for horizontal 39 and vertical beam deflection, each one connected to a fast power supply. The dose delivery system exploits a set of monitor 40 chambers to measure the fluence and position of the beam and drives the beam during the treatment by controlling the sequence 41 of currents set by the power supplies. A test of the dynamic performance of the scanning system has been performed using a Hall 42 probe to measure the field inside the magnet and the results are presented in this paper. 43 44

Dosimetric characterization of a microDiamond detector in clinical scanned carbon ion beams

“…Full technological and clinical details about the CNAO are reported elsewhere. 18,[30][31][32] In particular, for the absorbed dose to water determination under reference conditions and, consequently, the beam monitor calibration, the IAEA-TRS 398 recommendations 17 were used, adapted following the formalism proposed by Jäkel et al 33 to take into account the specificities of particle pencil beam scanning. Reference conditions included the use of a Farmertype ionization chamber calibrated under Co-60 beams at a standard dosimetry laboratory (SSDL), monoenergetic beams, homogeneous 6 × 6 cm 2 scanned fields, and the measurement depth of 2 cm in water.…”

The CNAO dose delivery system for modulated scanning ion beam radiotherapy

“…The details of construction and performances are reported in [20] and references therein; here we give a short summary …”

“…5,9 The details of construction and performances have been reported in Ref. 21 and references therein; here, we give only a short summary focusing on the aspects which are more relevant to the DDS and the related clinical requirements.…”

Commissioning operations and performances of the Dose Delivery system for CNAO

“…An important role is played by the interface with the timing system that synchronizes the Dose Delivery System with several events connected with the accelerating cycle. A FPGA card controls the scanning magnet power supplies currents directly via an optical connection at a rate of 40 kHz [4]. The safety of the treatment relies on dedicated interlock system (PIS) where anomalous conditions detected by the DD induce the immediate interruption of the beam delivery.…”