Compact tunable Compton x-ray source from laser-plasma accelerator and plasma mirror

Abstract

We present an in-depth experimental-computational study of the parameters necessary to optimize a tunable, quasi-monoenergetic, efficient, low-background Compton backscattering (CBS) x-ray source that is based on the self-aligned combination of a laser-plasma accelerator (LPA) and a plasma mirror (PM). The main findings are: (1) an LPA driven in the blowout regime by 30 TW, 30 fs laser pulses producesnot only a high-quality, tunable, quasi-monoenergetic electron beam, but also a high-quality, relativistically intense (a0~1) spent drive pulse that remains stable in profile and intensity over the LPA tuning range. (2) A thin plastic film near the gas jet exit retro-reflects the spent drive pulse efficiently into oncoming electrons to produce CBS x-rays without detectable bremsstrahlung background. Meanwhile anomalous far-field divergence of the retro-reflected light demonstrates relativistic "denting" of the PM. Exploiting these optimized LPA and PM conditions, we demonstrate quasi-monoenergetic (50% FWHM energy spread), tunable (75 to 200 KeV) CBS x-rays, characteristics previously achieved only on more powerful laser systems by CBS of a split-off, counter-propagating pulse. Moreover, laser-to-x-ray photon conversion efficiency ~6e12 exceeds that of any previous LPA-based quasi-monoenergetic Compton source. Particle-in-cell simulations agree well with the measurements.

10 pages, 7 figures

References in corpus (6)

• Femtosecond x rays from laser-plasma accelerators
• All-optical Compton gamma-ray source
• Enhancement of electron energy to multi-GeV regime by a dual-stage laser-wakefield accelerator pumped by petawatt laser pulses
• Ultra-high brilliance multi-MeV $\gamma$-ray beam from non-linear Thomson scattering
• Optical Properties of Relativistic Plasma Mirrors
• Enhancement of laser-driven electron acceleration in an ion channel

Cited by in corpus (12)

• Experimental evidence of radiation reaction in the collision of a high-intensity laser pulse with a laser-wakefield accelerated electron beam
• Highly efficient laser-driven Compton gamma-ray source
• An all-optical Compton source for single-exposure X-ray imaging
• Effects of Laser Polarization and Color on Hybrid Laser Wakefield and Direct Acceleration
• Optimal Parameters for Radiation Reaction Experiments
• Self-aligning concave relativistic plasma mirror with adjustable focus
• Synchrotron radiation from a curved plasma channel laser wakefield accelerator
• Radiation emission from braided electrons in interacting wakefields
• A nonlinear plasma retroreflector for single pulse Compton backscattering
• Quasi-monochromatic bright gamma-ray generation from synchronized Compton scattering via azimuthal spatial-temporal coupling
• The optimum conditions of laser field depletion in laser-electron beam collision
• A Platform for All-optical Thomson/ Compton Scattering with Versatile Parameters