Optical Shaping of Plasma Cavity for Controlled Laser Wakefield Acceleration

Laser wakefield accelerators rely on relativistically moving micron-sized plasma cavities that provide extremely high electric field >100GV/m. Here, we demonstrate transverse shaping of the plasma cavity to produce controlled sub-GeV electron beams, adopting laser pulses with an axially rotatable ellipse-shaped focal spot. We showed the control capability on electron self-injection, charge, and transverse profile of the electron beam by rotating the focal spot. We observed that the effect of the elliptical focal spot was imprinted in the profiles of the electron beams and the electron energy increased, as compared to the case of a circular focal spot. We performed 3D particle-in-cell (PIC) simulations which reproduced the experimental results and revealed dynamics of a new asymmetric self-injection process. This simple scheme offers a novel control method on laser wakefield acceleration to produce tailored electron beams and x-rays for various applications.Comment: 5 pages, 5 figure

Laser wakefield electron acceleration with PW lasers and future applications

© 2022, The Korean Physical Society.Laser wakefield acceleration (LWFA), owing to its large acceleration field, is a promising method for overcoming the limitations of radio-frequency linear accelerators. Recent demonstrations of petawatt (PW) lasers have afforded opportunities for further advancing research on LWFA. The research group at the ultrashort quantum beam facility (UQBF), Advanced Photonics Research Institute (APRI), Gwangju institute of science and Technology (GIST), developed PW lasers in 2010 and successfully applied these PW lasers to LWFA. LWFA research involving PW lasers was succeeded by the Center for Relativistic Laser Science (CoReLS), Institute for Basic Science (IBS). In this review, we summarize the research results from UQBF and CoReLS pertaining to LWFA.11Nsciescopuskc

Bright muon source driven by GeV electron beams from a compact laser wakefield accelerator

We report here a systematic quantitative study on the generation and characteristics of an active muon source driven by the interaction of an electron beam within the energy range of 1-10 GeV from laser wakefield acceleration (LWFA) with a tungsten target, using Monte Carlo simulations. The 10 GeV electron beam, achievable in the near future, from LWFA using femtosecond multi-PW lasers is employed to drive the bright source of muon pairs in a compact setup. We show that a highly directional and intense source of short-pulsed GeV muon pairs (μ - μ +) have a peak brightness of 5 × 1017 pairs s-1cm-2sr-1 and sub-100 ps duration could be produced using a quasi-monoenergetic 10 fs, 10 GeV electron bunch with a 1-mrad divergence and 100 pC charge. The muon pairs are emitted from a point-like source with a well-defined position and timing; the source has a size and geometric emittance of about 1 mm and 40 μm, respectively. Such muon sources can greatly benefit applications in muon radiography as well as studies on anomalous dipole moments, rare decays of muons, neutrino oscillations, and an injector for a future compact muon collider. © 2018 IOP Publishing Lt