Accelerator Based Neutron Capture Therapies in France

Exposé oralInternational audienceIn France, we have started in 2015, an interdisciplinary work on AB-NCT profiting of a synergy among different research institutes: Laboratoire de Physique Subatomique et de Cosmologie de Grenoble (LPSC), the Institut Laue-Langevin (ILL) and the Institut de Physique Nucléaire de Lyon (IPNL) coming from nuclear physics, with neutron and gamma detection expertise and their medical applications, the Grenoble University Hospital (CHU) and the Institut Albert Bonniot (IAB) coming from radiobiology, biological research, and clinical experience.The main purpose of this collaboration is to enable the production of epithermal neutron fields in a hospital environment by contributing to the development of compact (accelerator based) neutron sources. In parallel, we plan to improve the understanding of the biophysical determinants of the effectiveness of treatment performing radiobiology studies by cell irradiations at the ILL and simulation modelling (see R. Delorme et al. contribution). In addition, a particular effort will be performed to understand and optimize the deleterious effects of AB-NCT on tumor cells and to characterize the potential induction of subsequent anti-tumor immune responses.Since the beginning of the project, the major realizations have been:- a rotating Be target design able to cope with 30 kW (20 mA of deuteron beam at 1.5 MeV) and on the thermal tests with an electron beam using the COMICAC facility at LPSC,- the design of a Beam Shaping Assembly (BSA) adapted to this rotating target,- the development of a neutron directional detection system to characterize and control the neutron fields before and during the NCT irradiation.We will present the fast neutron directional detector (MIMAC-FastN) able to characterize the fluence and the angular distribution of the neutron fields produced. Using a thin foil of natB inside the active volume, we can calibrate the detector with the same reaction that will be produced at the tumor level. We will show results of measurements of fast neutrons performed recently. We will present the design and thermal simulations of the original rotating target, with in situ regeneration capability, and the BSA adapted to it.All these contributions will be placed in the context of a national project profiting of know-how on high current ion sources and RFQ availabilities