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arXiv · 2206.07962

Beam focus modifications by cropping partially coherent X-ray beams

Manuel Sanchez del Rio·Rafael Celestre·Juan Reyes-Herrera·Philipp Brumund·Marco Cammarata
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Abstract

We simulate the focusing of a partially-coherent X-ray beam emitted by an undulator in a fourth-generation storage ring performing coherent mode decomposition and wave optics propagation. The focus position is shifted, and its size is enlarged when an entrance slit crops the beam. This is the usual case when a slit is used to select the coherent fraction. The pairing of two focusing elements (mirrors, lenses or transfocators) to ensure a fixed focal position is also analyzed. Our results show that the image of a partially coherent source, such an undulator in a low-emittance storage ring, is a non-trivial function of the aperture used to control the coherence fraction.

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Manuel Sanchez del Rio, Rafael Celestre, Juan Reyes-Herrera, Philipp Brumund, Marco Cammarata. 2022-06-16. Beam focus modifications by cropping partially coherent X-ray beams. https://doi.org/10.1209/0295-5075%2Faca4ef

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