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arXiv · 0908.0677

Broad-Band Soft X-ray Polarimetry

Herman L. Marshall·Ralf Heilmann·Norbert Schulz·Kendrah Murphy
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Abstract

We developed an instrument design capable of measuring linear X-ray polarization over a broad-band using conventional spectroscopic optics. A set of multilayer-coated flats reflects the dispersed X-rays to the instrument detectors. The intensity variation with position angle is measured to determine three Stokes parameters: I, Q, and U -- all as a function of energy. 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 > 50% over the entire 0.2 to 0.8 keV band. This instrument could be used in a small orbiting mission or scaled up for the International X-ray Observatory. Laboratory work has begun that would demonstrate the capabilities of key components.

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Herman L. Marshall, Ralf Heilmann, Norbert Schulz, Kendrah Murphy. 2009-08-05. Broad-Band Soft X-ray Polarimetry. https://doi.org/10.1117/12.857443

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