Low energy ion beam monitoring system by dosimetry film and particle induced X-ray

A simple monitoring system for a low energy (less than 5 MeV) proton beam by dosimetry film was developed. A few μm thick Ni foil was installed in front of the film to produce X-rays which develop the film. To eliminate heat damage by the ion beam, a Ni foil was prepared on a 500 μm thick graphite sheet which stops the ion beam and effectively dissipates the heat transversely. To verify the linearity of development, 1–2.5 MeV proton beams were irradiated at various fluences, and the irradiated films were analyzed by a UV–VIS spectrometer and a commercial film scanner. The system showed a good linearity of absorbance in the fluence range from 4.6 × 1013 H+/cm2 to 1 × 1015 H+/cm2 for 2.5 MeV protons. The irradiated film showed a two-dimensional profile of the ion beam very well with a spatial resolution of about 2.8 mm.