The Decadal Survey Testbed: Demonstrating Technology for Imaging Earth-like Exoplanets with Future Space Telescopes

The NASA Exoplanet Exploration Program's Decadal Survey Testbed (DST), one of three coronagraph testbeds in the High Contrast Imaging Testbed facility at the Jet Propulsion Laboratory, aims to the demonstrate the coronagraph technologies required to directly image and characterize Earth-like exoplanets with future NASA space telescopes. Commissioned in early 2019, the DST has become NASA's most sensitive coronagraph testbed with a vacuum environment and high thermal/vibrational stability. We have demonstrated a Lyot coronagraph with two deformable mirrors, a Nickel-on-glass occulting spot, and annular Lyot stop that provide a 360° dark hole between 3 to 9 λ/D at 550 nm using Electric Field Conjugation wavefront control algorithms. The DST coronagraph achieved repeatable convergence below 5e-10 mean raw contrast within a spectral bandwidth of Δλ/λ=0.1. This testbed is now available to all principal investigators awarded openly-competed NASA Strategic Astrophysics Technology grants. In this talk, I will describe the testbed design, raw contrast results in both monochromatic and polychromatic light, empirical testbed stability, current testbed limitations, and plans for future experiments.