Design and realization of a beam transport line for handling and selecting laser-driven ion beams for multidisciplinary applications

Hadrontherapy is currently considered to be one of the most advanced and precise external radiotherapy techniques for tumour treatment. Unfortunately, it availability is still very limited worldwide despite considerable clinical evidence in its favor. The main reasons for this are huge costs for construction, installation and maintenance associated with complex accelerators (mostly cyclotrons and synchrotrons, and, in general, technical complexity of the facility management and the fact that other radiation therapies have a longer history of use. The use of more compact hadrontherapy approaches would obviously have a valuable impact on society. Laser-plasma ion acceleration is a new field of Physics rapidly evolving thanks to the continuing development of high power laser systems, thus allowing to investigate the interaction of ultrahigh laser intensities with matter. As a result of such interaction, extremely high electric and magnetic fields are generated which can accelerate ion with several tens of MeV. Such non-conventional acceleration schemes have been intensively investigated in the last 15 years and the field is rapidly growing thanks to the continuing development of high power laser systems. The main goal of the laser-driven ion acceleration community is to deliver reliable and very compact approaches to be possibly used for societal applications, with the aim of reducing the overall cost of standard accelerator facilities. In order to overcome the existing challenges new laser technologies have to be exploited, in particular enabling simultaneously high peak power (multi-Petawatt) and high repetition rate (up to 10 Hz) which are about to be available at ELI-Beamlines (Dolní Břežany, Czech Republic). As an example of possible advantages of a laser-based approach, transporting the laser pulse to the treatment rooms to generate the ion source closer to the patient would drastically reduce costs related to ion beamlines. Furthermore, laser-based hadron radiotherapy would uniquely offer the option of synchronous delivery of multiple beams of photons, electrons and different ion species (e.g., He and C ions), with enhanced capabilities for mixed field irradiations, an approach also of interest to cancer therapy. This work focuses on the design, development and installation of the beamline for selecting and handling the ion beams that will be accelerated at the ELI-Beamlines in the dedicated experimental hall ELIMAIA (ELI multidisciplinary applications of laser-ion acceleration). The beamline, partially characterized with conventionally accelerated beams, represents an extremely compact accelerator of 10m length (from the laser-target interaction point to the irradiation point) that would allow users to perform experiments using the unique ion beams accelerated with Peta-watt class laser available at ELI-Beamlines, with particular care for dosimetric and irradiation studies. Moreover, a cenceptual design for upgrading the core element of the beamline (the energy selector) is presented. This upgrade would allow to use the device also as a Thomson Parabola spectrometer which is a fundamental diagnostics for laser-driven ion beams. This spectrometer would allow to analyze ions with energies of few hundreds of MeV per nucleons with considerably high precision.