Development of X-ray Optics Technology for Future Indian Astronomy Missions at PRL

At the Physical Research Laboratory (PRL), Ahmedabad, India, we have initiated the development of X-ray optics for future Indian X-ray astronomy telescopes. As part of this initiative, we have established an RF magnetron sputtering system for multilayer thin-film coating on X-ray mirrors. Currently, we employ the thermal glass slumping method to fabricate thin, segmented glass substrates with geometries similar to Wolter-I optics, as used in the NuSTAR mission. To characterize the multilayer coating parameters, an X-ray reflectivity (XRR) measurement system from Anton Paar has been established, and the DarpanX software has been developed to analyze the measured data. In addition, the DarsakX software has been developed to design and analyze the imaging performance of multishell X-ray telescopes. Furthermore, a Fizeau interferometer–based metrology system is being set up to measure the surface figure of segmented X-ray mirror foils, which are shaped close to cylinders. This paper provides an overview of the technological developments related to X-ray optics at PRL.