Title: Refractive/diffractive telescope with very high angular resolution for X-ray astronomy
Abstract: The 0.5 arcsec angular resolution of the Chandra X-Ray Observatory is likely to be the best that a grazing incidence telescope with substantial collecting area will ever attain. We describe a concept for a telescope composed of diffractive and refractive components that transmit rather than reflect X-rays. Therefore, its angular resolution would be relatively insensitive to figure errors and surface roughness. With appropriately selected values for the two focal lengths the chromatic aberration that is inherent in both the diffractive and refractive components individually would compensate each other within a limited but not insignificant energy band. The system has a focal length of about 10<sup>4</sup> km because the refractive component is rather weak. The long focal length requires a very demanding type of formation flying between an optics spacecraft and a detector spacecraft. We simulate the simplest diffractive/refractive imaging system where chromatic aberration is corrected to first order at 6 keV. The angular resolution is expected to be better than a miliarcsec within a 10 % bandwidth. The energy band could be broadened either by employing an array of smaller systems with the same total area or by modifying the diffractive component in situ. The components are lightweight, not difficult to fabricate and can probably be made in a machine shop. We also consider possible sites for the system.
Publication Year: 2005
Publication Date: 2005-08-18
Language: en
Type: article
Indexed In: ['crossref']
Access and Citation
Cited By Count: 10
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot