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

Journal Article · Tue Oct 23 00:00:00 UTC 2018 · Physical Review E

DOI: https://doi.org/10.1103/physreve.98.043206 · OSTI ID:1612294

Miao, B. ^[1]; Feder, L. ^[2]; Elle, J. ^[2]; Goers, A. J. ^[2]; Woodbury, D. ^[2]; Salehi, F. ^[2]; Wahlstrand, J. K. ^[2]; Milchberg, H. M. ^[2]

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1. Univ. of Maryland, College Park, MD (United States); DOE/OSTI
2. Univ. of Maryland, College Park, MD (United States)

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 <~1μm. Under certain conditions, the radiation occurs at harmonics of the local plasma frequency. The flash is sufficiently bright to induce large nonlinear refractive index shifts in optical materials; we estimate a source brightness temperature of ~10¹⁸K. We present measurements of the flash spectra, coherence, pulse duration, polarization, and angular distribution, providing a detailed picture of electron injection dynamics in LWFA. Furthermore, these are characteristic of laser-assisted injection of off-axis electrons, which preserves wake coherence.

• Research Organization: Univ. of Maryland, College Park, MD (United States)
• Sponsoring Organization: USDOE; USDOE Office of Science (SC)
• Grant/Contract Number: SC0015516
• OSTI ID: 1612294
• Journal Information: Physical Review E, Journal Name: Physical Review E Journal Issue: 4 Vol. 98; ISSN 2470-0045
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English