Ultra-brilliant GeV betatronlike radiation from energetic electrons oscillating in frequency-downshifted laser pulses

Abstract

Electrons can be accelerated to GeV energies with high collimation via laser wakefield acceleration in the bubble regime and emit bright betatron radiation in a table-top size. However, the radiation brightness is usually limited to the third-generation synchrotron radiation facilities operating at similar photon energies. Using a two-stage plasma configuration, we propose a novel scheme for generating betatronlike radiation with an extremely high brilliance. In this scheme, the relativistic electrons inside the bubble injected from the first stage can catch up with the frequency-downshifted laser pulse formed in the second stage. The laser red shift originates from the phase modulation, together with the group velocity dispersion, which enables more energy to be transfered from the laser pulse to γ-photons, giving rise to ultra-brilliant betatronlike radiation. Multi-dimensional particle-in-cell simulations indicate that the radiated γ-photons have the cut-off energy of GeV and a peak brilliance of 1026 photons s−1 mm−2 mrad−2 per 0.1%BW at 1 MeV, which may have diverse applications in various fields.

Intense Mid-Infrared Laser Pulse Generated via Flying-Mirror Red-Shifting in Near-Critical-Density Plasmas

“…Recently, plasma-based methods without damage threshold limit have been demonstrated to be able to yield strong MIR light. [16] It has been proposed that the photon deceleration in wakefield, [17][18][19][20][21] and Doppler upshift from terahertz light [22] are feasible to produce relativistic MIR sources.…”

Characteristic diagnosis of supersonic gas jet target for laser wakefield acceleration with high spatial-temporal resolution Nomarski interference system

“…reduce the energy spread of accelerated beams [9][10][11]29,30]. Therefore, it is very suitable as an experimental target for laser wakefield acceleration [25,31,32], laser-driven betatron [33][34][35][36] and gamma radiation source [37][38][39][40], etc.…”