Upcoming Events

CfAI Seminar Programme: Wednesday 20th March OCW017 1pm

Mark Corrigan: Low order wavefront sensing with photonic lanterns

Nicolas Dubost: Closing a control loop with a point-diffraction interferometer Summary: In high-contrast adaptive optics, point-diffraction interferometers (PDI) have been proposed to accurately measuring quasi-static aberrations, cophasing segmented mirrors, dealing with the island problem and even acting as main WFSs in XAO systems. Here we report on the results of the integration of our own PDI, CAWS, into CHOUGH, the Durham high-order adaptive optics system. Closed-loop experiments with static aberrations were performed with both monochromatic and polychromatic light. With monochromatic light, PSF measurements showed Strehl ratio increases from 0.20 to 0.66. Preliminary broadband light tests with a FWHM of ∆λ=12% (80 nm) also showed a reduction of residual errors and an improvement of Strehl, which proves the polychromatic capabilities of CAWS. Initial simulation results are also presented, to study the necessary conditions to close a control loop on-sky.

CfAI is one of the major research groups in the Physics Department at Durham with approximately 70 staff and research students. It is distributed across two physical locations, one of which is in the new Ogden Centre for Fundamental Physics on the University science site in Durham, and the other is at the North East Technology Park (NETPark), an internationally recognised location for science and technology companies, based about ten miles away in Sedgefield, Co. Durham.

CfAI develops state-of-the-art instruments for application across a wide range of disciplines including astronomical instrumentation, biophysics, remote sensing and fusion diagnostics. Research outputs can be found by following the links to individual research areas listed in the menu on the left or by a search of Durham Research Online. We also have close links with the Centre for Extragalactic Astronomy and the Institute for Computational Cosmology.