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arXiv · 0912.5331

A wide field X-ray telescope for astronomical survey purposes: from theory to practice

P. Conconi·S. Campana·G. Tagliaferri·G. Pareschi·O. Citterio·V. Cotroneo·L. Proserpio·M. Civitani
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Abstract

X-ray mirrors are usually built in the Wolter I (paraboloid-hyperboloid) configuration. This design exhibits no spherical aberration on-axis but suffers from field curvature, coma and astigmatism, therefore the angular resolution degrades rapidly with increasing off-axis angles. Different mirror designs exist in which the primary and secondary mirror profiles are expanded as a power series in order to increase the angular resolution at large off-axis positions, at the expanses of the on-axis performances. Here we present the design and global trade off study of an X-ray mirror systems based on polynomial optics in view of the Wide Field X-ray Telescope (WFXT) mission. WFXT aims at performing an extended cosmological survey in the soft X-ray band with unprecedented flux sensitivity. To achieve these goals the angular resolution required for the mission is very demanding ~5 arcsec mean resolution across a 1-deg field of view. In addition an effective area of 5-9000 cm^2 at 1 keV is needed.

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P. Conconi, S. Campana, G. Tagliaferri, G. Pareschi, O. Citterio, V. Cotroneo, L. Proserpio, M. Civitani. 2010-02-11. A wide field X-ray telescope for astronomical survey purposes: from theory to practice. https://doi.org/10.1111/j.1365-2966.2010.16513.x

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