ESCAPE project: testing active observing strategies for high-contrast imaging in space on the HiCAT testbed

TL;DR

This paper explores active observing strategies using deformable mirrors to improve high-contrast imaging for exoplanet detection in space, validated through experiments on the HiCAT testbed.

Contribution

It introduces novel methods for probing wavefront variations and optimizing starlight subtraction using a PSF library, tested on the HiCAT platform.

Findings

Successful application of wavefront probing methods on HiCAT

Improved starlight subtraction techniques demonstrated

Validation of active observing strategies for space-based imaging

Abstract

The Roman Space Telescope will be a critical mission to demonstrate high-contrast imaging technologies allowing for the characterisation of exoplanets in reflected light. It will demonstrate $10^{-7}$ contrast limits or better at 3--9 $\lambda / D$ separations with active wavefront control for the first time in space. The detection limits for the Coronagraph Instrument are expected to be set by wavefront variations between the science target and the reference star observations. We are investigating methods to use the deformablel mirrors to methodically probe the impact of such variations on the coronagraphic PSF, generating a PSF library during observations of the reference star to optimise the starlight subtraction at post-processing. We are collaborating with STScI to test and validate these methods in lab using the HiCAT tested, a high-contrast imaging lab platform dedicated to system-level developments for future space missions. In this paper, we will present the first applications of these methods on HiCAT.