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arXiv · 0709.2343

A Soft X-ray Polarimeter Designed for Broad-band X-ray Telescopes

Herman L. Marshall
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Abstract

A novel approach for measuring linear X-ray polarization over a broad-band using conventional imaging optics and cameras is described. A new type of high efficiency grating, called the critical angle transmission grating is used to disperse soft X-rays radially from the telescope axis. A set of multilayer-coated paraboloids re-image the dispersed X-rays to rings in the focal plane. The intensity variation around these rings 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 50% over the entire 0.2 to 0.8 keV band. A sample design is shown that could be used with the Constellation-X optics.

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Herman L. Marshall. 2007-09-14. A Soft X-ray Polarimeter Designed for Broad-band X-ray Telescopes. https://doi.org/10.1117/12.746957

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