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arXiv · 1807.04165

Coherent ultra-broadband laser-assisted injection radiation from a laser plasma accelerator

B. Miao·L. Feder·J. Elle·A. J. Goers·D. Woodbury·F. Salehi·J. K. Wahlstrand·H. M. Milchberg
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Abstract

The injection of electrons into a laser wakefield accelerator (LWFA) is observed to generate an intense coherent ultra-broadband and ultrashort pulse radiation flash, consistent with the acceleration of electrons from rest to nearly the speed of light in a distance < ~ 1 $μ$m. The flash is sufficiently bright to induce large nonlinear refractive index shifts in optical materials; we estimate a source brightness temperature of ~$10^{18}$ K. We present measurements of the flash spectra, coherence, pulse duration, polarization and angular distribution, providing a detailed picture of electron injection dynamics in LWFA. These are characteristic of laser-assisted injection of off-axis electrons, which preserves wake coherence.

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B. Miao, L. Feder, J. Elle, A. J. Goers, D. Woodbury, F. Salehi, J. K. Wahlstrand, H. M. Milchberg. 2018-09-29. Coherent ultra-broadband laser-assisted injection radiation from a laser plasma accelerator. https://doi.org/10.1103/physreve.98.043206

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