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arXiv · 0809.2928

Polarimetry with a soft x-ray spectrometer

Herman L. Marshall
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Abstract

An approach for measuring linear X-ray polarization over a broad-band using conventional spectroscopic optics is described. A set of multilayer-coated flats reflect the dispersed X-rays to the instrument detectors. The intensity variation as a function of energy and position angle is measured to determine three Stokes parameters: I, Q, and U. By laterally grading the multilayer optics and matching the dispersion of the gratings, one may take advantage of high multilayer reflectivities and achieve modulation factors over 80% over the entire 0.2 to 0.8 keV band. A sample design is shown that could be used with a small orbiting mission.

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Herman L. Marshall. 2008-09-17. Polarimetry with a soft x-ray spectrometer. https://doi.org/10.1117/12.787249

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