Preliminary investigations of a potential optics system for wideband X-ray telescopes

Preliminary investigations of a potential optics system for wideband X-ray telescopes are performed in this work. The optics design adopts the conical approximation to Wolter-I configuration and the technique combination of multilayer coatings and silicon pore optics. The total number of mirror modules is 79 distributed in 8 rows with the radii at the intersection plane between 250 mm and 500 mm. The optimization of the total effective area using the figure of merits method suggests that the focal length is 30 m and the mirror coating is a combination of the W/Si and Pt/C multilayers. It fulfills the on-axis effective area requirements of 2000 cm² at 10 keV and 300 cm² at 60 keV and provides a broad energy response between 3 keV and 78.4 keV. With the current geometry and coating recipes, a mass modeling of the telescope is implemented in Geant4 to predict the mirror performances via the ray-tracing algorithm, including the angular resolution and effective area. With the presumed metrological data as input, it can provide precision and finishing requirements for optics manufacturing. This work demonstrates the feasibility of the technique combination of multilayer coating and silicon pore optics for its potential usage in wideband X-ray telescopes and advances the development and progress of such missions.