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arXiv · 0802.0237

Knot undulator to generate linearly polarized photons with low on-axis power density

S. Qiao·Dewei Ma·Donglai Feng·Z. Hussain·Z. -X. Shen
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Abstract

Heat load on beamline optics is a serious problem to generate pure linearly polarized photons in the third generation synchrotron radiation facilities. For permanent magnet undulators, this problem can be overcome by a figure-8 operating mode. But there is still no good method to tackle this problem for electromagnetic elliptical undulators. Here, a novel operating mode is suggested, which can generate pure linearly polarized photons with very low on-axis heat load. Also the available minimum photon energy of linearly polarized photons can be extended much by this method.

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S. Qiao, Dewei Ma, Donglai Feng, Z. Hussain, Z. -X. Shen. 2008-02-02. Knot undulator to generate linearly polarized photons with low on-axis power density. https://doi.org/10.1063/1.3204452

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