Polarization transfer in Rayleigh scattering of hard x-rays

K-H Blumenhagen,A Surzhykov,S Trotsenko,T Stöhlker,D Seipt,N Schell,R Märtin,A Gumberidze,T Gassner,S Fritzsche,U Spillmann,V A Yerokhin,G Weber

doi:10.1088/1367-2630/18/10/103034

Abstract

We report on the first elastic hard x-ray scattering experiment where the linear polarization characteristics of both the incident and the scattered radiation were observed. Rayleigh scattering was investigated in a relativistic regime by using a high-Z target material, namely gold, and a photon energy of 175 keV. Although the incident synchrotron radiation was nearly 100% linearly polarized, at a scattering angle of we observed a strong depolarization for the scattered photons with a degree of linear polarization of only. This finding agrees with second-order quantum electrodynamics calculations of Rayleigh scattering, when taking into account a small polarization impurity of the incident photon beam which was determined to be close to 98%. The latter value was obtained independently from the elastic scattering by analyzing photons that were Compton-scattered in the target. Moreover, our results indicate that when relying on state-of-the-art theory, Rayleigh scattering could provide a very accurate method to diagnose polarization impurities in a broad region of hard x-ray energies.

Highlights

Elastic scattering of hard x-rays by atoms is a fundamental process which is usually described as a coherent sum of scattering from the individual atomic constituents
In order to perform this non-trivial summation over many-electron states, we employed the independent particle approximation (IPA) in which the photon is scattered by a single active electron at a time, while the remaining electrons are kept ‘frozen’ [43, 58]
The polarization transfer in Rayleigh scattering of highly linearly polarized hard x-rays was studied at the synchrotron radiation source PETRA III

Summary

23 November 2016

K-H Blumenhagen, S Fritzsche, T Gassner, A Gumberidze, R Märtin, N Schell, D Seipt1,. Helmholtz-Institut Jena, Fróbelstieg 3, D-07743 Jena, Germany the terms of the Creative 2 GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, D-64291 Darmstadt, Germany. Commons Attribution 3.0 3 Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, D-07743 Jena, Germany licence. In the abstract it says that at θ = 90°, a degree of polarization of +0.27% ± 0.12% was measured. This number should be +27% ± 12%.

20 October 2016

Introduction

Experiment

Data analysis

Results and discussion

Conclusion and outlook