Paper 14145-181
Paper 14145-181
Enhanced wavefront sensing for Roman CGI: alternative probes with flight-like validation
7 July 2026 • 17:30 - 19:00 CEST | Room B4-M3
Abstract
The Coronagraph Instrument (CGI) on the Roman Space Telescope will be the first space-based system to demonstrate closed-loop focal-plane wavefront sensing and control, a key step towards HWO. Beyond the baseline Hybrid Lyot Coronagraph, “enhanced modes” are being developed to improve efficiency and science yield. One such mode uses gaussian probes for electric field probing, extending the linear regime and allowing higher probe amplitudes without estimator bias. This may increase signal-to-noise, reduce exposure time, accelerate dark-hole convergence, and extend operation to stars as faint as V~5. The Coronagraph Community Participation Program’s Hardware Working Group is validating this enhancement using the corgihowfsc control software and a PROPER-based optical model of CGI. We show simulation results where this may show faster convergence and resilience to DM nonlinearities, supporting alternative probing as a low-risk, high-gain improvement for Roman CGI and future missions.
Presenter
Lukas Delaye
Observatoire de Paris à Meudon (France)
I am currently a first-year PhD student at LIRA, a laboratory at the Paris Observatory, where I am studying direct imaging of exoplanets for the future Roman Space Telescope. I work with Axel Potier, Johan Mazoyer, and Pierre Baudoz. My thesis aims to study and optimize innovative techniques such as active correction (dark hole) or post-processing correction (coherence differential imaging) applied to the Roman Space Telescope's coronagraph through numerical simulations and laboratory work on the THD2 bench at Meudon. In particular, I have continued the work undertaken on the alternative probing for the Roman Space Telescope since the beginning of my thesis.