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Significant challenges in the detection of laser-accelerated ions result from the high flux (1010-1012 ions/pulse) and the short bunch duration which are intrinsic to laser-driven sources. The development of diagnostic techniques able to operate in real-time and on a high-rep basis is a key step towards multidisciplinary applications of such non-conventional beams. Real time diagnosis of the main beam parameters for high-energy protons accelerated by the Vulcan Petawatt (VULCAN-PW) laser system has been performed using an on line diagnostics based on the Time of Flight (TOF) technique and the use of diamond detectors. Proton energy spectra have been measured for energies exceeding 30 MeV. The results show that the TOF method employing state-of-the-art detectors is a robust real-time diagnostics, able to operate efficiently under the harsh conditions occurring with kJ-class, PW laser systems, and offering the possibility to monitor on a shot-by-shot basis the main beam parameters of high intensity proton bunches for energies up to the 100 MeV level.

International audience; The Time-of-Flight (TOF) technique coupled with semiconductorlike detectors, as silicon carbide and diamond, is one of the most promising diagnostic methods for high-energy, high repetition rate, laser-accelerated ions allowing a full on-line beam spectral characterization. A new analysis method for reconstructing the energy spectrum of high-energy laser-driven ion beams from TOF signals is hereby presented and discussed. The proposed method takes into account the detector’s working principle, through the accurate calculation of the energy loss in the detector active layer, using Monte Carlo simulations. The analysis method was validated against well-established diagnostics, such as the Thomson parabola spectrometer, during an experimental campaign carried out at the Rutherford Appleton Laboratory (UK) with the high-energy laser-driven protons accelerated by the VULCAN Petawatt laser.

The tissue-equivalent proportional counter (TEPC) is the most accurate device for measuring the microdosimetric properties of a particle beam but, since the lower operation limit of common TEPCs is ~0.3 μm, no detailed information on the track structure of the impinging particles can be obtained. The pattern of particle interactions at the nanometric level is measured directly by only three different nanodosimeters worldwide: practical instruments are not yet available. In order to partially fill the gap between microdosimetry and track-nanodosimetry, a low-pressure avalanche-confinement TEPC was designed and constructed for simulating tissue-equivalent sites down to the nanometric region. The present paper aims at describing the response of this TEPC in the range 0.3 μm-25 nm to a 62 MeV/n 4He ion beam. The experimental results, for depths near the Bragg peak, show good agreement with FLUKA simulations and suggest that, for smaller depths, the distribution is highly influenced by secondary electrons.

The ELIMED (MEDical and multidisciplinary application at ELI Beamlines) beam line is being developed at INFN-LNS with the aim of transporting and selecting in energy proton and ion beams accelerated by laser-matter interaction at ELI Beamlines in Prague. It will be a section of the ELIMAIA (ELI Multidisciplinary Applications of laser-Ions Acceleration) beam line, dedicated to applications, including the medical one, of laser-accelerated ion beams [1,2]. A Monte Carlo model has been developed to support the design of the beam line in terms of particle transport efficiency, to optimize the transport parameters at the irradiation point in air and, furthermore, to predict beam parameters in order to deliver dose distributions of clinical relevance. The application has been developed using the Geant4 [3] Monte Carlo toolkit and has been designed in a modular way in order to easily switch on/off geometrical components according to different experimental setups and users requirements, as reported in [4], describing the early-stage code and simulations. The application has been delivered to ELI Beamlines and will be available for future ELIMAIA's users as ready-to-use tool useful during experiment preparation and analysis. The final version of the developed application will be described in detail in this contribution, together with the final results, in terms of energy spectra and transmission efficiency along the in-vacuum beam line, obtained by performing end-to-end simulations., Comment: EAAC 2017 proceeding NIM A

Nowadays the innovative high power laser-based ion acceleration technique is one of the most interesting challenges in particle acceleration field, showing attractive characteristics for future multidisciplinary applications, including medical ones. Nevertheless, peculiarities of optically accelerated ion beams make mandatory the development of proper transport, selection and diagnostics devices in order to deliver stable and controlled ion beams for multidisciplinary applications. This is the main purpose of the ELIMAIA (ELI Multidisciplinary Applications of laser-Ion Acceleration) beamline that will be realized and installed within 2018 at the ELI-Beamlines research center in the Czech Republic, where laser driven high energy ions, up to 60 MeV/n, will be available for users. In particular, a crucial role will be played by the on-line diagnostics system, recently developed in collaboration with INFN-LNS (Italy), consisting of TOF detectors, placed along the beamline (at different detection distances) to provide online monitoring of key characteristics of delivered beams, such as energy, fluence and ion species. In this contribution an overview on the ELIMAIA available ion diagnostics will be briefly given along with the preliminary results obtained during a test performed with high energy laser-driven proton beams accelerated at the VULCAN PW-laser available at RAL facility (U.K.).

Laser-accelerated ion beams could represent the future of particle acceleration in several multidisciplinary applications, as for instance medical physics, hadrontherapy and imaging field, being a concrete alternative to old paradigm of acceleration, characterized by huge and complex machines. In this framework, following on from the ELIMED collaboration, launched in 2012 between INFN-LNS and ELI-Beamlines, in 2014 a three-years contract has been signed between the two institutions for the design and the development of a complete transport beam-line for high-energy ion beams (up to 60 MeV) coupled with innovative diagnostics and in-air dosimetry devices. The beam-line will be installed at the ELI-Beamlines facility and will be available for users. The measurement of the beam characteristics, such as energy spectra, angular distributions and dose-rate is mandatory to optimize the transport as well as the beam delivery at the irradiation point. In order to achieve this purpose, the development of appropriate on-line diagnostics devices capable to detect high-pulsed beams with high accuracy, represents a crucial point in the ELIMED beamline development. The diagnostics solution, based on the use of silicon carbide (SiC) and diamond detectors using TOF technique, will be presented together with the preliminary results obtained with laser-accelerated proton beams.

A growing interest of the scientific community towards multidisciplinary applications of laser-driven beams has led to the development of several projects aiming to demonstrate the possible use of these beams for therapeutic purposes. Nevertheless, laser-accelerated particles differ from the conventional beams typically used for multiscipilinary and medical applications, due to the wide energy spread, the angular divergence and the extremely intense pulses. The peculiarities of optically accelerated beams led to develop new strategies and advanced techniques for transport, diagnostics and dosimetry of the accelerated particles. In this framework, the realization of the ELIMED (ELI-Beamlines MEDical and multidisciplinary applications) beamline, developed by INFN-LNS (Catania, Italy) and that will be installed in 2017 as a part of the ELIMAIA beamline at the ELI-Beamlines (Extreme Light Infrastructure Beamlines) facility in Prague, has the aim to investigate the feasibility of using laser-driven ion beams for multidisciplinary applications. In this contribution, an overview of the beamline along with a detailed description of the main transport elements as well as the detectors composing the final section of the beamline will be presented.

ELI (Extreme Light Infrastructure) multidisciplinary applications of laser-ion acceleration (ELIMAIA) is one the user facilities beamlines of the ELI-Beamlines facility in Prague. It will be dedicated to the transport of laser-driven ion beams and equipped with detectors for diagnostics and dosimetry, in order to carry out experiments for a broad range of multidisciplinary applications. One of the aims of the beamline is also to demonstrate the feasibility of these peculiar beams for possible medical applications, which means delivering controllable and stable beams, properly monitoring their transport parameters and accurately measuring the dose per shot. To fulfil this task, innovative systems of charged particle beam diagnostics have been realized and alternative approaches for relative and absolute dosimetry have been proposed. Concerning the first one, real-time diagnostic solutions have been adopted, involving the use of time-of-flight techniques and Thomson parabola spectrometry for an on-line characterization of the ion beam parameters, as well as radiochromic films, nuclear track detectors (typically CR39), and image plates for single shot measurements. For beam dosimetry, real-time beam/dose monitoring detectors have been realized, like the secondary emission monitor and a double-gap ionization chamber, which can be cross calibrated against a Faraday cup, used for absolute dosimetry. The main features of these detectors are reported in this work together with a description of their working principle and some preliminary tests.

The main direction proposed by the community of experts in the field of laser-driven ion acceleration is to improve particle beam features (maximum energy, charge, emittance, divergence, monochromaticity, shot-to-shot stability) in order to demonstrate reliable and compact approaches to be used for multidisciplinary applications, thus, in principle, reducing the overall cost of a laser-based facility compared to a conventional accelerator one and, at the same time, demonstrating innovative and more effective sample irradiation geometries. The mission of the laser-driven ion target area at ELI-Beamlines (Extreme Light Infrastructure) in Dolní Břežany, Czech Republic, called ELI Multidisciplinary Applications of laser-Ion Acceleration (ELIMAIA), is to provide stable, fully characterized and tuneable beams of particles accelerated by Petawatt-class lasers and to offer them to the user community for multidisciplinary applications. The ELIMAIA beamline has been designed and developed at the Institute of Physics of the Academy of Science of the Czech Republic (IoP-ASCR) in Prague and at the National Laboratories of Southern Italy of the National Institute for Nuclear Physics (LNS-INFN) in Catania (Italy). An international scientific network particularly interested in future applications of laser driven ions for hadrontherapy, ELI MEDical applications (ELIMED), has been established around the implementation of the ELIMAIA experimental system. The basic technology used for ELIMAIA research and development, along with envisioned parameters of such user beamline will be described and discussed.

Nowadays, one of the biggest challenges consists in using high intensity laser-target interaction to generate high-energy ions for medical purposes, eventually replacing the old paradigm of acceleration characterized by huge and complex machines. In order to investigate the feasibility of using laser-driven ion beams for multidisciplinary application, a dedicated beam transport line will be installed at the ELI-Beamlines facility in Prague (CZ), as a part of the User-oriented ELIMAIA beam-line dedicated to ion acceleration and their potential applications. The beam-line section dedicated to transport and dosimetric endpoints is called ELIMED (ELI-Beamlines MEDical and multidisciplinary applications) and will be developed by the INFN-LNS.