Quantum radiation reaction in aligned crystals beyond the local constant field approximation

T. N. Wistisen, A. Di Piazza, C. F. Nielsen +2

We report on experimental spectra of photons radiated by 50 GeV positrons crossing silicon single crystals of thicknesses 1.1 mm, 2.0 mm, 4.2 mm, and 6.2 mm at sufficiently small a…