SCREENED CHAMBER FOR ION THERAPY WITH PROTECTION AGAINST NEUTRONS HAVING ENERGY UP TO GEV

摘要

A screened chamber, the therapy chamber, for ion therapy with neutrons having energy up to GeV is disclosed. The above is provided with screening on all but one sides and has a labyrinthine access on the non-screened side. The labyrinthine access comprises two shieldings longitudinally offset in the radiation axis and extending from opposing sides into the chamber, each of which covers more than half the open width of the access. The shieldings are embodied to be suitable to induce a spallation process with the incident neutron and the neutrons produced can be moderated. According to the invention, the central shielding measure is a combination shielding, comprising metal and a hydrogen-containing layer. High energy neutrons, caused by the so-called spallation reactions are generated, which are weakened in the second and further layers.