Principles of laser–plasma accelerators

Abstract

The continuing development of powerful laser systems has permitted to extend the interaction of laser beams with matter far into the relativistic domain in which extremely high electric and magnetic fields are generated. Thanks to these tremendous fields, that only plasma can support and sustain, new and compact approaches for producing energetic particle beams have been recently achieved. The incredible progress of these laser-plasma accelerators has allowed physicists to produce high quality beams of energetic radiation and particles. These beams have interesting properties such as shortness, brightness and spatial quality, and could lend themselves to applications in many fields, including medicine (radiotherapy, proton therapy, imaging), radiation biology (short-time-scale), chemistry (radiolysis), physics and material science (radiography, electron and photon diffraction), security (material inspection), and of course accelerator science. Stimulated by the advent of compact and powerful lasers, with moderate costs and high repetition rate, this research field has witnessed considerable growth in the past few years, and the promises of laserplasma accelerators are in tremendous progress. The recent years in particular have seen spectacular progress in the acceleration of electrons and of ions, both in terms of energy and in terms of quality of the beams.

Manipulation of laser-accelerated proton beam profiles by nanostructured and microstructured targets

“…top laser systems, using the chirped-pulse amplification (CPA) technique, which were developed in the last decades, are able to reach ultrahigh intensities (above 10 18 W=cm 2 ) through the generation of femtosecond laser pulses [1], thus offering new possibilities in the study of relativistic laser-matter interactions [2,3]. Among others, laser-driven ion acceleration is one of the most promising and intensively investigated research topics [4], where target normal sheath acceleration (TNSA) is the experimentally most investigated technique. TNSA is based on the relativistic interaction of a thin target and an intense laser pulse and can be used to accelerate protons to several tens of MeV [5][6][7][8].…”

Ultra‐high dose rate radiation production and delivery systems intended for FLASH

“…In the following years, significant breakthroughs, including the “dream beams” with quasi‐monoenergetic electron distribution, 73–75 were demonstrated, and just after that, a stable monoenergetic electron beam with adjustable parameters (such as electron energy and charge) was demonstrated 76 . These breakthroughs show the potential of LPAs for societal applications 77 and have triggered more exploration towards RT applications.…”

“…Courtesy of Prof. U. Schramm, Institute for Radiation Physics and Oncoray, Helmholtz-Zentrum Dresden-Rossendorf, Germany were demonstrated, and just after that, a stable monoenergetic electron beam with adjustable parameters (such as electron energy and charge) was demonstrated. 76 These breakthroughs show the potential of LPAs for societal applications 77 and have triggered more exploration towards RT applications. Today, typical working conditions of LPAs in delivering VHEE RT are a PRF of 1 Hz in routine (or of 10 Hz occasionally, because of the lifetime of the expensive gratings), tens to hundreds of pC charge in the 250 MeV energy range (within a suitable few MeV energy bandwidth), which should allow reaching about 20 cm depth, at 50 Gy in 1 min, in 1 cm 3 volume.…”

Towards a PWFA linear collider — opportunities and challenges

“…Part of this energy can be used to accelerate a trailing beam, which, in case of a collider, is the "main beam" to be collided. The driver can be a high-intensity laser beam where the ponderomotive force of the laser pulse drives a plasma wake [16,17], or a charged particle beam, where the space charge forces drive the wake [18,19]. As discussed above, power efficiency is of the essence for any Multi-TeV collider.…”