Line Spread Functions of Blazed Off-Plane Gratings Operated in the Littrow Mounting

Casey T. DeRoo; Randall L. McEntaffer; Drew M. Miles; Thomas J. Peterson; Hannah Marlowe; James H. Tutt; Benjamin D. Donovan; Benedikt Menz; Vadim Burwitz; Gisela Hartner; Ryan Allured; Randall K. Smith; Ramses Gunther; Alex Yanson; Giuseppe Vacanti; Marcelo Ackermann

arXiv · 1603.04839

Line Spread Functions of Blazed Off-Plane Gratings Operated in the Littrow Mounting

Casey T. DeRoo·Randall L. McEntaffer·Drew M. Miles·Thomas J. Peterson·Hannah Marlowe·James H. Tutt·Benjamin D. Donovan·Benedikt Menz·Vadim Burwitz·Gisela Hartner·Ryan Allured·Randall K. Smith·Ramses Gunther·Alex Yanson·Giuseppe Vacanti·Marcelo Ackermann

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Abstract

Future soft X-ray (10 - 50 Angstrom) spectroscopy missions require higher effective areas and resolutions to perform critical science that cannot be done by instruments on current missions. An X-ray grating spectrometer employing off-plane reflection gratings would be capable of meeting these performance criteria. Off-plane gratings with blazed groove facets operated in the Littrow mounting can be used to achieve excellent throughput into orders achieving high resolutions. We have fabricated two off-plane gratings with blazed groove profiles via a technique which uses commonly available microfabrication processes, is easily scaled for mass production, and yields gratings customized for a given mission architecture. Both fabricated gratings were tested in the Littrow mounting at the Max-Planck-Institute for extraterrestrial Physics PANTER X-ray test facility to assess their performance. The line spread functions of diffracted orders were measured, and a maximum resolution of 800 $\pm$ 20 is reported. In addition, we also observe evidence of a `blaze' effect from measurements of relative efficiencies of the diffracted orders.

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Casey T. DeRoo, Randall L. McEntaffer, Drew M. Miles, Thomas J. Peterson, Hannah Marlowe, James H. Tutt, Benjamin D. Donovan, Benedikt Menz, Vadim Burwitz, Gisela Hartner, Ryan Allured, Randall K. Smith, Ramses Gunther, Alex Yanson, Giuseppe Vacanti, Marcelo Ackermann. 2016-03-15. Line Spread Functions of Blazed Off-Plane Gratings Operated in the Littrow Mounting. https://arxiv.org/abs/1603.04839

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