One of the biggest problems for telescopes placed on the ground are the optical aberrations produced by the atmospheric turbulence when observing sky objects. Fortunately, technological progress made possible the development of Adaptive Optics, a technique which enables real-time correction of the atmospheric distortions, hence providing improved image quality to the scientific instruments in the telescope. Thanks to adaptive optics we are capable to identify planets outside the solar system and also to observe the motion of stars around the black holes in the center of our galaxy.
A key technology in adaptive optics are lasers that can produce bright spots of light in the upper atmosphere, also called laser guide stars. Laser guide stars are essential to extend the observable sky where adaptive optics can be employed, providing astronomer with more and better information about the universe.
In this project, we investigated methods and technologies that tackle the fundamental limitations of laser guide stars in current and future adaptive optics systems. We studied how a multi-color laser guide star can be generated and evaluated how this could enable an adaptive optics system to correct for the fast lateral motion (jitter) of stars arising from atmospheric turbulence. We contributed to the development of the PAPYRUS adaptive optics bench, which has been in operation at the Observatoire de Haute-Provence in southern France, providing a pyramid-based adaptive optics system to the whole community for experimenting new concepts and technology. In addition, we developed a prototype of a laser guide star wavefront sensor for one of the first instruments of the Extremely Large Telescope. This prototype helped to validate a new wavefront sensor camera and to test the optical design of the wavefront sensor for the first time in a controlled environment. This part of the work provided valuable information for the final design of the laser guide star wavefront sensor.
