Nonlinear Inverse Compton Scattering from a Laser Wakefield Accelerator and Plasma Mirror

A. Hannasch; M. LaBerge; R. Zgadzaj; J. P. Couperus Cabadağ; A. Laso Garcia; T. Kurz; T. Cowan; U. Schramm; A. Irman; M. C. Downer

arXiv · 2107.00139

Nonlinear Inverse Compton Scattering from a Laser Wakefield Accelerator and Plasma Mirror

A. Hannasch·M. LaBerge·R. Zgadzaj·J. P. Couperus Cabadağ·A. Laso Garcia·T. Kurz·T. Cowan·U. Schramm·A. Irman·M. C. Downer

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Abstract

We generate inverse Compton scattered X-rays in both linear and nonlinear regimes with a 250 MeV laser wakefield electron accelerator and plasma mirror by retro-reflecting the unused drive laser light to scatter from the accelerated electrons. We characterize the X-rays using a CsI(Tl) voxelated scintillator that measures their total energy and divergence as a function of plasma mirror distance from the accelerator exit. At each plasma mirror position, these X-ray properties are correlated with the measured fluence and inferred intensity of the laser pulse after driving the accelerator to determine the laser strength parameter $a_0$. The results show that ICS X-rays are generated at $a_0$ ranging from $0.3\pm0.1$ to $1.65\pm0.25$, and exceed the strength of co-propagating bremsstrahlung and betatron X-rays at least ten-fold throughout this range of $a_0$.

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A. Hannasch, M. LaBerge, R. Zgadzaj, J. P. Couperus Cabadağ, A. Laso Garcia, T. Kurz, T. Cowan, U. Schramm, A. Irman, M. C. Downer. 2021-06-30. Nonlinear Inverse Compton Scattering from a Laser Wakefield Accelerator and Plasma Mirror. https://arxiv.org/abs/2107.00139

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