A high resolution large x-ray mission based on thin glass: optomechanical design

The technology of X-ray optics based on very thin glass sheets curved on mandrels figured to an optical quality have been quickly developed in these last years, as the on flight NUSTAR or the glass solutions for the IXO mission have demonstrated. Different possibilities to freeze the correct shape can be chosen and the constrains to the glass can widely affect the response in term of strength and quality. This study shows the opto-mechanical performances of the design based on the hot slumped glass sheets stiffed with reinforcing ribs. With this concept a glass stack can be integrated into a mechanical structure in order to form a module that can be assembled in a large structure. The considered input data and requirements are those specified for the proposed Athena mission. Different types of materials are considered following the latest progress in the slumping and the availability of alternative tougher glass. Static and dynamic FE analyses coupled with ray-tracing are performed in order to reach a high resolution (less than 5 arcsec). Also an optimization of the ribs distribution is implemented in function of the radius of curvature.