Patent ID: 8859980

Claim:
A device for on line dosimetry monitoring of a hadron beam generated from a source of radiation and delivered to a target, the device comprising: a plurality of support plates arranged in parallel, separated from each other by gas filled gaps and positioned perpendicularly to the central axis of said hadron beam, and forming a plurality of ionization chambers, each support plate having on a first side one or more collecting electrodes and on a second side one or more voltage electrode, arranged in such a way that the first side of a support plate of said plurality of support plates is opposed to the second side of subsequent support plate, wherein each support plate has an opening so as to form an inner cavity for allowing an undisturbed passage of a central portion of the hadron beam delivered to said target and a peripheral region for intercepting and measuring, by means of said plurality of ionization chambers, a peripheral portion of said hadron beam.