Simultaneousmeasurements of dose and microdosimetric spectra in a clinical proton beam using a scCVD diamond membrane microdosimeter

Oluwasayo Loto (1) , Izabella Zahradnik (1) , Amelia Maia Leite (2) , Ludovic de Marzi (2) , Dominique Tromson (3) , Michal Pomorski (1)

1 LCD (CEA, LIST) - Laboratoire Capteurs Diamant (CEA, LIST)
2 Institut Curie [Paris]
3 LCAE (CEA, LIST) - Laboratoire Capteurs et Architectures Electroniques (CEA, LIST)

A single crystal chemical vapor deposition (scCVD) diamond membrane-based microdosimetric system was used to perform simultaneous measurements of dose profile and microdosimetric spectra with the Y1 proton passive scattering beamline of the Center of Proton Therapy, Institute Curie in Orsay, France. To qualify the performance of the set-up in clinical conditions of hadrontherapy, the dose, dose rate and energy loss pulse-height spectra in a diamond microdosimeter were recorded at multiple points along depth of a water-equivalent plastic phantom. The dose-mean lineal energy ($\overline{y}_D$) values were computed from experimental data and compared to silicon on insulator (SOI) microdosimeter literature results. In addition, the measured dose profile, pulse height spectra and $\overline{y}_D$ values were benchmarked with a numerical simulation using TOPAS and Geant4 toolkits. These first clinical tests of a novel system confirm that diamond is a promising candidate for a tissue equivalent, radiation hard, high spatial resolution microdosimeter in beam quality assurance of proton therapy.

Mots clés: diamond; Chemical Vapor Deposition (CVD); single crystal chemical vapor deposition; dosimetry; microdosimetry; instrumentation; nuclear instrumentation; dose measurement; dose profile; microdosimetric spectra; proton; Proton Therapy; hadrontherapy; dose rate; dose; energy loss; diamond microdosimeter; phantom; radiation detectors; sensor; simulation; TOPAS; Geant4; particle transport; Monte Carlo; ionizing radiation; metrology; pulse-height spectra

Domaines: Instrumentations et Détecteurs [physics.ins-det]

Oluwasayo Loto, Izabella Zahradnik, Amelia Maia Leite, Ludovic de Marzi, Dominique Tromson, et al.. Simultaneousmeasurements of dose and microdosimetric spectra in a clinical proton beam using a scCVD diamond membrane microdosimeter. Sensors, 2021, 21 (4), pp.1314. ⟨10.3390/s21041314⟩. ⟨cea-04551117⟩