Proposal Project

PROPOSAL PROJECT DEREP “Characterization and DEvelopment of a stable and REproducible scheme for laser-driven Proton sources” Principal Investigator: Dr. Luca Volpe Scientific coordinator: Prof. Dario Giove ISTITUTO NAZIONALE DI FISICA NUCLEARE Concorso per il Finanziamento di n. 1 progetto per giovani ricercatrici/ricercatori nell’ambito delle Linee di ricerca della Commissione Scientifica Nazionale 5 Abstract In this project we propose to study possible stable configurations for producing laser-driven proton beams with a maximum energy around 40-50 MeV by using well established national and international laser facilities of reasonable complexity, cost and size and also to design a “micro” transport line for collimation and energy selection of the proton beam . This could represent the first scheme for a future prototype of laser-driven proton beam system for medical applications. The Europen project ELIMED seems to be the natural framework in which the proposal can be developed DEREP 1. Project objectives Interest in laser driven proton acceleration continues to be strong since 2000, with a potentially wide range of applications among which the most important are that related to medical applications. The importance of laser and target advancements for source optimization has been made clear by many laser- plasma interaction experiments done in laboratories around the world. The development of suitable instrumentation and beam lines that can exploit the unique features of laser- accelerated proton emission is critical and timely. Since 2000 tremendous fundamental research and development have been performed on laser-driven proton and ion sources, even if a lot of long-term effort is still required for the implementation of laser-driven medical accelerators: i) the proton acceleration mechanisms and the target conditions should be optimized in order to obtain the beam energy, spectrum and divergence which match well the desired application requirements ii) the design of a “micro scaled” proton beam transport line is an important issue to makes these type of sources usable for medical application. In this context the goal of this project is to study possible stable configurations for producing laser-driven proton beams with a maximum energy around 40-50 MeV by using “conventional laser systems” and also to design a “micro” transport line. This could represent the first scheme for a future prototype of laser -driven proton beam system for medical applications. As will be explained in the following this project can be thought as part of an European project ELIMED (Extreme Light Infrastructure Medicine) which was proposed by the National Institute of Nuclear Physics [It] (INFN) within the framework of the European project ELI (Extreme Light Infrastructure) which aim is to build a new generation of large research facilities selected by the European Strategy Forum for Research Infrastructures (ESFRI). The aim of the ELIMED project is to perform proof-of-principle experiments (in 1-10 Hz regime) which might demonstrate the validity of new approaches, based on laser-driven proton sources, for potential future applications in the field of hadron-therapy. It also involves contributes from many worldwide institutions that expressed a strong interest in this new pioneering field. The hope of this new community is to give in the next years, a new vital impulse to the tumor radiation treatments with ion beams. Stable laser-driven proton (ions) source is demanded principally for medical application but also for many other applications among which the most relevant are: i) proton imaging of matter by using mono energetic beam obtained by chromatic selection of the proton sources; ii) proton imaging (proton radiography) of imploding plasma and proton mapping of elctric and magnetic fields (proton deflectometry) in the context of the inertial confinement approach to nuclear fusion. Moreover the broad energy spectrum of laser-driven proton beam permit to follows plasma implosion in time (proton time of flight); iii) warm and hot dense matter generation. Indeed thanks to the Bragg peak property of protons is possible to warm up the matter from inside; iv) nuclear and particle physics: the interaction of laser-driven high-energy ions with secondary targets can initiate nuclear reactions of various types can be used as a tool to diagnose the beam properties. This also presents the opportunity of carrying out nuclear physics experiments in laser laboratories rather than in accelerator or reactor facilities, and to apply the products of the reaction processes in several areas. To reach the goal of the project we focus on three main items: 1) Proton source development 2) Beam Transport Design 3) Beam Instrumentation development. The source development activities will be focused on the study of the processes involved in the design, construction and alignment of specific targets. These activities will take as “reference” laser facilities able to deliver beams with energies of at least 5-10 J, contrast of the order of 109-1010, pulse duration of the order of 100 fs, focal spot of the order of 20 micron (FWHM), intensity of the order of 10 19 at least. Lasers with these characteristics may be considered of reasonable complexity, cost and size. Experimental results obtained by Ogura and collaborators in 2012 and reported in ref [Ogura2012] can be used as “reference case” . By using 40 fs laser pulse duration, 1021 W /cm2 and irradiating targets of 800 nm thickness, they reported proton energies up to 40 MeV, the highest value reported so far for pulse energies below 10 J. Within this framework, once the main laser parameters are fixed, the performance of the laser-generated proton beams can be studied as follows : 1) Controlling target properties. → Reducing target density down to the critical density to enhance laser absorption (foams) → Reducing target thickness (thin targets ) Page 2 of 19 DEREP → reducing target area (mass limited targets) → modifying target surface geometry (cone shaped targets) → using multilayer targets (foam+solid or with tracers to reveal Ka emission) 2) Controlling chamber set-up → Laser diagnostic tools → Target Positioning 3) Controlling transport of the laser-genereted proton beam: → designing “micro-scaled” transport device for laser-driven proton beam based on quadrupole magnets for treatment of the incoming proton beam and for selection minimization of other secondary particle (electrons and photons) production. Developing this project will includes experimental and theoretical work. The theoretical work will be dedicated to numerical simulations connected to laser-matter interaction as well as electron generation and transport for target design, design of a “micro-scaled” transport device (magnetic quadrupole or solenoid) for ion beam transport and for chromatic energy selection. The experimental work will be the main part of the project. In particular the definition of an experimental campaign will be the first step of the project and all the other activities will be connect to that. Several physical regimes are involved in this type of processes which require using different physical models and approaches at the same time. This makes collaboration between different laboratories and different institutions very profitable. Therefore “collaboration” with other institutions and laboratories represent one of the key point of the project. Within the framework of this project, two different scientific areas are naturally involved: the physic of High energy lasers and the physics of accelerators. It is a matter of fact that connecting two different areas of science will lead, naturally to new advancements and open new scientific opportunities. One example of that is the recent installation of the new femto-second Laser system called FLAME (Frascati Laser for Acceleration and Multidisciplinary Experiments) [FLAME] at the National Laboratories of Frascati beside the per-existence Free Electron Laser. As anticipated before the natural context of the outlined project is the European ELIMED project by INFN [It], therefore, within national context, the main collaboration will be with the INFN Section of Milano (Carlo De Martini and Dario Giove) and with the INFN section of Bologna (Giorgio Turchetti) as well as with the National laboratory of Frascati in which the laser FLAME is located. Indeed Laser Flame is one of the laser facilities considered for possible experiment in this project. Milano and Bologna sections have a long collaboration in many national and international projects as for example ELIMED. For target preparation the project will also profit from collaboration with Prof. P. Piseri at the molecular beams laboratory of CIMaINa and Physics Department of the Università degli Studi di Milano, that will provide expertise on the synthesis of nanostructured material layers via supersonic cluster beam deposition (SCBD) [MIlani2001]. This technique allows the deposition of porous material from carbon, metal or oxide nano-particles. The PI and the group of Prof. Piseri collaborated in 2012 for an experiment in Accademy of Science in Bejing China which aim was to study carbon target thickness and density optimization for relativistic electron transport in matter. On the other hand the international collaboration will be started with the theoretical and experimental group of the research center CELIA at the University of Bordeaux for numerical simulations and experimental support, with the group of prof. I. Hofmann of the

Load more