Isaac Ghebregziabher

TL;DR: In this article, quasi-monoenergetic Compton X-rays tunable in the range ∼70 keV to > 1 MeV are generated in a laser-driven scheme.

TL;DR: The generation of MeV x rays using an undulator and accelerator that are both driven by the same 100-terawatt laser system is reported, and the x-ray photon energy exceeds the thresholds of fundamental nuclear processes.

TL;DR: In this paper, a relativistic, three-dimensional numerical model was developed to calculate and quantify the characteristics of emitted radiation when an electron beam interacts with an intense laser pulse.

Abstract: Stable operation of a laser-plasma accelerator near the threshold for electron self-injection in the blowout regime has been demonstrated with 25–60 TW, 30 fs laser pulses focused into a 3–4 millimeter length gas jet. Nearly Gaussian shape and high nanosecond contrast of the focused pulse appear to be critically important for controllable, tunable generation of 250–430 MeV electron bunches with a lowenergy spread, � 10 pC charge, a few-mrad divergence and pointing stability, and a vanishingly small low-energy background. The physical nature of the near-threshold behavior is examined using threedimensional particle-in-cell simulations. Simulations indicate that properly locating the nonlinear focus of the laser pulse within the plasma suppresses continuous injection, thus reducing the low-energy tail of the electron beam.

TL;DR: In this article, a scalable high-energy electron source based on laser wakefield acceleration is presented, which produces high-quality, quasi-monoenergetic electron beams in the range 100-800 MeV.