Plastic scintillator investigations for relative dosimetry in proton-therapy

Plastic organic scintillators, polyvinyltoluene based, can be used with hig h sensitivity to detect 1-60 MeV proton beams. Thin scintillators can be ap plied to proton-therapy field as relative dosimeter thanks to their water-e quivalent nature, high energy-light conversion efficiency, low dimensions a nd good proportionality to the absorbed dose at low stopping powers. Unfort unately, the quenching effect limits the use of tee scintillators at high s topping powers. Moreover, they show a negligible radiation damage at the ty pical proton doses used in radiotherapy. Preliminary results have been obta ined detecting in air both 60 MeV therapeutically proton beam at the Paul S cherrer Institute (PSI, Villigen-Zurich) and 24 MeV proton beam, at the Lab oratorio Nazionale del Sud (LNS, Catania). (C) 2000 Elsevier Science B.V. A ll rights reserved.