Pupil-plane LLOWFS simulation and laboratory results from NEW-EARTH’s high-contrast imaging testbed

Garima Singh; William Thompson; Olivier Lardière; Christian Marois; Mamadou N'Diaye; Adam B. Johnson; Jean-Pierre Véran; Glen Herriot; Benjamin Gerard; Qiang Fu; Wolfgang Heidrich

doi:10.1117/12.2627977

29 August 2022 Pupil-plane LLOWFS simulation and laboratory results from NEW-EARTH’s high-contrast imaging testbed

Garima Singh, William Thompson, Olivier Lardière, Christian Marois, Mamadou N'Diaye, Adam B. Johnson, Jean-Pierre Véran, Glen Herriot, Benjamin Gerard, Qiang Fu, Wolfgang Heidrich

Author Affiliations +

Proceedings Volume 12185, Adaptive Optics Systems VIII; 1218553 (2022) https://doi.org/10.1117/12.2627977
Event: SPIE Astronomical Telescopes + Instrumentation, 2022, Montréal, Québec, Canada

Conference Poster

Abstract

Direct imaging of exoplanets can be used to characterize exoplanets by spectroscopy of their atmospheres. Coronagraphs are required to suppress the diffraction effects by blocking the starlight, however, residual wavefront error scatters starlight in the science images, losing faint exoplanet photons in stellar noise. The performance of a coronagraphic system is thus contingent upon how efficiently the wavefront aberrations are minimized. Lyot-stop low-order wavefront sensor (LLOWFS) is a well-established sensor that senses the light rejected by the focal plane mask and corrects low-order aberrations upstream of the coronagraph. Previous versions of the LLOWFS sensed the residual starlight at the defocused focal plane. However, on the NRC's NEW-EARTH high-contrast imaging testbed, pupil-plane images of LLOWFS have been used to address both Zernike and Fourier modes. The goal of the testbed is to develop SPIDERS/Subaru which is the technology demonstrator of the CAL2 unit of the upcoming Gemini Planet Imager 2.0 (GPI 2.0). Both SPIDERS and CAL2 will address the low-order modes for stabilizing speckles, and demonstrate an active suppression of speckles using the Fast Atmospheric Self-Coherent Camera Technique (FAST) by creating a region of up to 10^-7 contrast at small angles. Thus, obtaining sub-nanometric pointing stability using the LLOWFS is crucial for achieving stable contrast results on the bench and on-sky. Here, we present LLOWFS closed-loop laboratory results under simulated post-Adaptive Optics residuals of GPI 2.0 and simulations of the LLOWFS and FAST sensors for SPIDERS.

Citation Download Citation

Garima Singh, William Thompson, Olivier Lardière, Christian Marois, Mamadou N'Diaye, Adam B. Johnson, Jean-Pierre Véran, Glen Herriot, Benjamin Gerard, Qiang Fu, and Wolfgang Heidrich "Pupil-plane LLOWFS simulation and laboratory results from NEW-EARTH’s high-contrast imaging testbed", Proc. SPIE 12185, Adaptive Optics Systems VIII, 1218553 (29 August 2022); https://doi.org/10.1117/12.2627977

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available