We investigated the dose-response of the external beam therapy 3 (EBT3) films for proton and carbon ion clinical beams, in comparison with conventional radiotherapy beams; we also measured the film response along the energy deposition-curve in water. We performed measurements at three hadrontherapy centres by delivering monoenergetic pencil beams (protons: 63-230 MeV; carbon ions: 115-400 MeV/u), at 0.4-20 Gy dose to water, in the plateau of the depth-dose curve. We also irradiated the films to clinical MV-photon and electron beams. We placed the EBT3 films in water along the whole depth-dose curve for 148.8 MeV protons and 398.9 MeV/u carbon ions, in comparison with measurements provided by a plane-parallel ionization chamber. For protons, the response of EBT3 in the plateau of the depth-dose curve is not different from that of photons, within experimental uncertainties. For carbon ions, we observed an energy dependent under-response of EBT3 film, from 16% to 29% with respect to photon beams. Moreover, we observed an under-response in the Bragg peak region of about 10% for 148.8 MeV protons and of about 42% for 398.9 MeV/u carbon ions. For proton and carbon ion clinical beams, an under-response occurs at the Bragg peak. For carbon ions, we also observed an under-response of the EBT3 in the plateau of the depth-dose curve. This effect is the highest at the lowest initial energy of the clinical beams, a phenomenon related to the corresponding higher LET in the film sensitive layer. This behavior should be properly modeled when using EBT3 films for accurate 3D dosimetry.

Measured cross sections for the production of the PET isotopes , and from carbon and oxygen targets induced by protons (40–220 ) and carbon ions (65–430 ) are presented. These data were obtained via activation measurements of irradiated graphite and beryllium oxide targets using a set of three scintillators coupled by a coincidence logic. The measured cross sections are relevant for the PET particle range verification method where accurate predictions of the emitter distribution produced by therapeutic beams in the patient tissue are required. The presented dataset is useful for validation and optimization of the nuclear reaction models within Monte Carlo transport codes. For protons the agreement of a radiation transport calculation using the measured cross sections with a thick target PET measurement is demonstrated.

Measured charge-and mass-changing cross sections for the systems 4 He + 12 C, 4 He + 16 O, 4 He + 28 Si, and 4 He + 1 H in the energy range 70-220 MeV/u are presented. The cross sections were obtained via the attenuation method where a E-E scintillator telescope was used for particle identification. These new data

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In the field of ion-beam radiotherapy and space applications, measurements of the energy deposition of single ions in thin layers are of interest for dosimetry and imaging. The present work investigates the capability of a pixelated detector Timepix to measure the energy deposition of single ions in therapeutic proton, helium- and carbon-ion beams in a 300 μm-thick sensitive silicon layer. For twelve different incident beams, the measured energy deposition distributions of single ions are compared to the expected energy deposition spectra, which were predicted by detailed Monte Carlo simulations using the FLUKA code. A methodology for the analysis of the measured data is introduced in order to identify and reject signals that are either degraded or caused by multiple overlapping ions. Applying a newly proposed linear recalibration, the energy deposition measurements are in good agreement with the simulations. The twelve measured mean energy depositions between 0.72 MeV/mm and 56.63 MeV/mm in a partially depleted silicon sensor do not deviate more than 7% from the corresponding simulated values. Measurements of energy depositions above 10 MeV/mm with a fully depleted sensor are found to suffer from saturation effects due to the too high per-pixel signal. The utilization of thinner sensors, in which a lower signal is induced, could further improve the performance of the Timepix detector for energy deposition measurements.