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arXiv · 1804.10061

Dispersive refraction of different light-to-heavy materials at MeV $γ$-ray energies

M. M. Günther·A. V. Volotka·M. Jentschel·S. Fritzsche·Th. Stöhlker·P. G. Thirolf·M. Zepf
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Abstract

The dispersive behavior of materials with atomic charge numbers varing from $Z = 4$ (beryllium, Be) to $Z = 82$ (lead, Pb) was investigated experimentally and theoretically at $γ$-ray energies up to 2 MeV. The experiment was performed at the double-crystal gamma spectrometer GAMS6 of the ILL in Grenoble. The experimental results were compared with theoretical calculations which account for all major elastic processes involved. Overall, we found a good agreement between theory and experiment. We find that for the development of refractive optics at $γ$-ray energies beyond those currently in use high-Z materials become increasingly attractive compared to the beryllium lens-stacks used at X-ray energies.

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M. M. Günther, A. V. Volotka, M. Jentschel, S. Fritzsche, Th. Stöhlker, P. G. Thirolf, M. Zepf. 2018-04-26. Dispersive refraction of different light-to-heavy materials at MeV $γ$-ray energies. https://doi.org/10.1103/physreva.97.063843

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