Broadband focal plane modal estimation of high-order wavefront drifts on coronagraphic testbeds

The Habitable Worlds Observatory (HWO) aims to directly image Exo-Earths 10 orders of magnitude dimmer than their host star. Algorithms such as dark zone maintenance (DZM) have been proposed to mitigate high-order wavefront drifts and maintain contrast. A modal dark zone maintenance (MDZM) approach, which represents and corrects drifting wavefronts in the deformable mirror (DM) actuator basis, has demonstrated improvement in closed-loop contrast performance by a factor of 5 in simulation in 2.5 in hardware. However, these results were confined to narrowband estimation and control. This work expands the MDZM formulation to use broadband images in simulation using the Decadal Survey Testbed (DST) simulator FALCO and in hardware using the In-Air Coronagraph Testbed (IACT) at NASA JPL. The resulting contrast performance is compared to traditional broadband DZM, as well as narrowband DZM and MDZM, across various drift rates and signal-to-noise ratios inside the dark zone of the speckles.