Laser ion sources are used to generate and deliver highly charged ions of various masses and energies We present details on the design and basic parameters of the DCU laser ion source (LIS) The theoretical aspects of a high voltage (HV) linear LIS are presented and the main issues surrounding laser-plasma formation, ion extraction and modeling of beam transport in relation to the operation of a LIS are detailed A range of laser power densities (I∼108–1011 W cm−2) and fluences (F=01–39 kJ cm−2) from a Q-switched ruby laser (full-width half-maximum pulse duration ∼35 ns, λ=694 nm) were used to generate a copper plasma In “basic operating mode,” laser generated plasma ions are electrostatically accelerated using a dc HV bias (5–18 kV) A traditional einzel electrostatic lens system is utilized to transport and collimate the extracted ion beam for detection via a Faraday cup Peak currents of up to I∼600 μA for Cu+ to Cu3+ ions were recorded The maximum collected charge reached 94 pC (Cu2+) Hydrodynam

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The DCU laser ion source

We have developed a novel laboratory instrument for studying gas phase, anion-neutral chemistry. To the best of our knowledge, this is the first such apparatus which uses fast merged beams to investigate anion-neutral chemical reactions. As proof-of-principle we have detected the associative detachment reaction H-+H -> H-2+e(-). Here we describe the apparatus in detail and discuss related technical and experimental issues.

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A novel merged beams apparatus to study anion-neutral reactions.

Within 2017, the ELIMED (ELI-Beamlines MEDical applications) transport beam-line and dosimetric systems for laser-generated beams will be installed at the ELI-Beamlines facility in Prague (CZ), inside the ELIMAIA (ELI Multidisciplinary Applications of laser–Ion Acceleration) interaction room. The beam-line will be composed of two sections: one in vacuum, devoted to the collecting, focusing and energy selection of the primary beam and the second in air, where the ELIMED beam-line dosimetric devices will be located. This paper briefly describes the transport solutions that will be adopted together with the main dosimetric approaches. In particular, the description of an innovative Faraday Cup detector with its preliminary experimental tests will be reported.

Transport and dosimetric solutions for the ELIMED laser-driven beam line

The CATANA protontherapy center was the first Italian clinical facility making use of energetic (62 MeV) proton beams for the radiative treatment of solid tumours. Since the date of the first patient treatment in 2002, 400 patients have been successful treated whose majority was affected by choroidal and iris melanomas. In this paper we report on the actual clinical and physical status of the CATANA facility describing the last dosimetric studies and reporting on the last patient follow-up results. The last part of the paper is dedicated to the description of the INFN ongoing activities on the realisation of a beamline for the transport of laser-accelerated ion beams. The ELIMED (ELI-BEamlines MEDical and multidisciplinary applications) project is intruded and its main scientific aspects described.

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Corrigendum: Clinical and Research Activities at the CATANA Facility of INFN-LNS: From the Conventional Hadrontherapy to the Laser-Driven Approach

Charged particle acceleration using ultra-intense and ultra-short laser pulses has gathered a strong interest in the scientific community and it is now one of the most attractive topics in the relativistic laser-plasma interaction research. Indeed, it could represent the future of particle acceleration and open new scenarios in multidisciplinary fields, in particular, medical applications. One of the biggest challenges consists of using, in a future perspective, high intensity laser-target interaction to generate high-energy ions for therapeutic purposes, eventually replacing the old paradigm of acceleration, characterized by huge and complex machines. The peculiarities of laser-driven beams led to develop new strategies and advanced techniques for transport, diagnostics and dosimetry of the accelerated particles, due to the wide energy spread, the angular divergence and the extremely intense pulses. In this framework, the realization of the ELIMED (ELI-Beamlines MEDical applications) beamline, developed by INFN-LNS (Catania, Italy) and 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 in multidisciplinary applications. ELIMED will represent the first user’s open transport beam line where a controlled laser-driven ion beam will be used for multidisciplinary and medical studies. In this paper, an overview of the beamline, with a detailed description of the main transport elements, will be presented. Moreover, a description of the detectors dedicated to diagnostics and dosimetry will be reported, with some preliminary results obtained both with accelerator-driven and laser-driven beams.

https://www.mdpi.com/2076-3417/5/3/427/pdf

Design and Status of the ELIMED Beam Line for Laser-Driven Ion Beams

Faraday cups (FCs) have long been used to measure charged particle beam currents in experiments that seek to determine cross-sections in energetic particle collisions. The reliable operation of a FC as a detector depends on the ability of the device to recapture the electrons ejected when energetic particles strike its interior metal surfaces. We have conducted comparative performance studies of a traditional cylindrically-symmetric, electrostatic-based FC versus an alternative design in which the cylindrical symmetry is broken. The purpose of the alternative design is to generate a transverse electric field to recapture the ejected (secondary and tertiary) electrons. The alternate FC design is shown to be superior in its ability to recapture these electrons, including those having kinetic energies greater than the potential energy barrier determined by the repeller voltage applied to the FC.

G.S. Hodges

Papers

Performance enhancement study of an electrostatic Faraday cup detector