Modeling coronagraphic extreme wavefront control systems for high contrast imaging in ground and space telescope missions

Abstract

The challenges of high contrast imaging (HCI) for detecting exoplanets for both ground and space applications can be met with extreme adaptive optics (ExAO), a high-order adaptive optics system that performs wavefront sensing (WFS) and correction at high speed. We describe two ExAO optical system designs, one each for groundbased telescopes and space-based missions, and examine them using the angular spectrum Fresnel propagation module within the Physical Optics Propagation in Python (POPPY) package. We present an end-to-end (E2E) simulation of the MagAO-X instrument, an ExAO system capable of delivering 6×10 −5 visible-light raw contrast for static, noncommon path aberrations without atmosphere. We present a laser guidestar (LGS) companion spacecraft testbed demonstration, which uses a remote beacon to increase the signal available for WFS and control of the primary aperture segments of a future large space telescope, providing on order of a factor of ten factor improvement for relaxing observatory stability requirements. The LGS E2E simulation provides an easily adjustable model to explore parameters, limits, and trade-offs on testbed design and characterization.

MagAO-X: project status and first laboratory results

“…A more detailed Fresnel propagation analysis is needed to test whether the PSDs of the optical surfaces allow the system to meet the contrast requirements. For details of this analysis see Lumbres et al in these proceedings, 33 where we find that as-designed MagAO-X will deliver 6 × 10 −5 raw contrast at Hα using the vAPP coronagraph.…”

An open-source gaussian beamlet decomposition tool for modeling astronomical telescopes

“…The capacity of this tool was later extended 6 to incorporate Fresnel diffraction, 22 which captures both the near and far-field effects that limit high-contrast imaging systems. 4 This implementation was used to model the Magellan Extreme Adaptive Optics upgrade (MagAO-X 23 ) but in order to model all the surfaces in the system the run time is significant ( 1 min per run).…”

MagAO-X first light

“…Here we provide a very brief overview of the MagAO-X design. See our previous SPIE contributions for more detailed treatments 1,[3][4][5][6][7][8][9][10][11][12] In addition, the complete preliminary design review (PDR) documentation is available at https://magao-x.org/docs/handbook/appendices/pdr/, and results of laboratory integration and preparation for shipment can be bound in the pre-ship review (PSR) documentation: https://magao-x.org/docs/ handbook/appendices/psr/index.html MagAO-X consists of a two-level floating optical table, used to mitigate vibrations, mounted on the gravityinvariant Nasmyth platform of the Magellan Clay 6.5 m telescope at Las Campanas Observatory (LCO), in Chile. See Figures 1 and 2.…”