Neeraj K. Tiwari, Santosh V. Vadawale, N. P. S. Mithun
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引用次数: 0
Abstract
Over the decades, astronomical X-ray telescopes have utilized the Wolter type-1 optical design, which provides stigmatic imaging in axial direction but suffers from coma and higher-order aberrations for off-axis sources. The Wolter-Schwarzschild design, with stigmatic imaging in the axial direction, while suffering from higher-order aberrations, is corrected for coma, thus performing better than the Wolter type-1. The Wolter type-1 and Wolter-Schwarzschild designs are optimized for on-axis but have reduced angular resolution when averaged over a wide field of view, with the averaging weighted by the area covered in the field of view. An optical design that maximizes angular resolution at the edge of the field of view rather than at the center is more suitable for wide-field X-ray telescopes required for deep-sky astronomical surveys or solar observations. A Hyperboloid-Hyperboloid optical design can compromise axial resolution to enhance field angle resolution, hence providing improved area-weighted average angular resolution over the Wolter-Schwarzschild design, but only for fields of view exceeding a specific size. Here, we introduce a new optical design that is free from coma aberration and capable of maximizing angular resolution at any desired field angle. This design consistently outperforms Wolter-1, Wolter-Schwarzschild, and Hyperboloid-Hyperboloid designs when averaged over any field of view size. The improvement in performance remains consistent across variations in other telescope parameters such as diameter, focal length, and mirror lengths. By utilizing this new optical design, we also present a design for a full-disk imaging solar X-ray telescope.
期刊介绍:
Many new instruments for observing astronomical objects at a variety of wavelengths have been and are continually being developed. Furthermore, a vast amount of effort is being put into the development of new techniques for data analysis in order to cope with great streams of data collected by these instruments.
Experimental Astronomy acts as a medium for the publication of papers of contemporary scientific interest on astrophysical instrumentation and methods necessary for the conduct of astronomy at all wavelength fields.
Experimental Astronomy publishes full-length articles, research letters and reviews on developments in detection techniques, instruments, and data analysis and image processing techniques. Occasional special issues are published, giving an in-depth presentation of the instrumentation and/or analysis connected with specific projects, such as satellite experiments or ground-based telescopes, or of specialized techniques.