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arXiv · 0908.4503

Coherent bremsstrahlung in a bent crystal

M. V. Bondarenco
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Abstract

Radiation spectrum from high energy $e^\pm$ in a bent crystal with arbitrary curvature distribution along the longitudinal coordinate is evaluated, based on the stationary phase approximation. For a uniformly bent crystal a closed-form expression for the spectrum is derived. Features such as sharp end of spectrum and volume reflection turnover at beginning of the spectrum are discussed. The coherence length in a bent crystal appears to depend only on the crystal geometry and not on the electron or photon energies, which is essential for interpretation of the results. Estimates of non-dipole radiation and multiple scattering effects are given. The value for the crystal bending angle at which the dipole coherent bremsstrahlung theory holds best appears to be $\sim 10^{-4}\mathrm{rad}$.

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M. V. Bondarenco. 2010-06-04. Coherent bremsstrahlung in a bent crystal. https://doi.org/10.1103/physreva.81.052903

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