Gamma-rays carrying orbital angular momenta produced by non-linear inverse Thomson scattering

We theoretically show that gamma-rays carrying orbital angular momenta (OAM) are produced by nonlinear inverse Thomson scattering. High energy electrons in intense circularly polarized light field undergo helical trajectories and radiate harmonic photons possessing helical phase structure and carrying OAM. This novel radiation mechanism would be the basis of OAM photon sources in high energy accelerators and, moreover, in various astrophysical environments. We show some numerical examples. Interactions of high energy OAM photons with atoms and nuclei may trigger new phenomena, which would open new research opportunities in nuclear physics, high energy physics and astrophysics.

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