The performance of thin shell adaptive optics for high angular resolution x-ray telescopes

Abstract

The Smart X-ray Optics project is a UK based consortium of five institutions investigating active/adaptive X-ray optics for both large and small scale applications. The large scale application is aimed towards future X-ray telescopes for X-ray astronomy. The work presented here includes the modelling and the testing of the new large scale prototype thin shell optic which incorporates piezoelectric devices to enable the surface to be actively deformed aiming to achieve an angular resolution better than that currently available (e.g. Chandra 0.5"). As the shell is thin, a high degree of nesting is possible such that very large collecting areas can be provided in combination with the high angular resolution. The results from the testing campaign for this prototype in the X-ray beam line at the University of Leicester will be presented. The effect of the actuated piezoelectric devices on the detected image and software development for control of the system are discussed. Improvement of the Full width Half Maximum of the focus spot of up to 25% was seen but as yet this has not been completed in a controlled way. The surface figure achieved with a given set of voltages is stable, but an apparent interaction or coupling between the piezoelectric devices was detected and is still unexplained.