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Kasdin, J.

Publications and source records attributed to Kasdin, J..

The Roman Space Telescope Coronagraph Technology Demonstration: Current Status and Relevance to Future Missions

The Nancy Grace Roman Space Telescope (formally WFIRST) will be launched in the mid-2020’s with an onboard coronagraph instrument which will serve as a technology demonstrator for exoplanet direct imaging. The Roman Coronagraph will be capable of detecting and characterizing exoplanets and circumstellar disks in visible light at an unprecedented contrast level of ~10-8 or lower. Such a contrast level, which is several magnitudes better than state-of-the-art visible or near-infrared coronagraphs, raises entirely new challenges that will be overcome using a combination of hardware, calibration and data processing. In particular, the Roman Coronagraph will be the first space-based coronagraphic instrument with real-time active wavefront control through the use of large format deformable mirrors, and its EMCCD detector will enable faint signal detection in photon-counting mode. The Roman Coronagraph passed its critical design review successfully in April 2021, and is now well on its path to demonstrate many core technologies at the levels required for future exo-Earth direct imaging missions.

Luchik, T.↗

The WFIRST Coronagraph Instrument: A Major Step in the Exploration of Sun-Like Planetary Systems Via Direct Imaging

The Wide Field Infrared Survey Telescope (WFIRST) Coronagraph Instrument (CGI) will be the first high-performance stellar coronagraph using active wavefront control for deep starlight suppression in space, providing unprecedented levels of contrast and spatial resolution for astronomical observations in the optical. One science case enabled by the CGI will be taking visible images and (R~50) spectra of faint interplanetary dust structures present in the habitable zone of nearby sunlike stars (~10 pc) and within the snow-line of more distant ones (~20 pc), down to dust brightness levels commensurate with that of the solar system zodiacal cloud. Reaching contrast levels below 10-7 at sub-arcsecond angular scales for the first time, CGI will cross an important threshold in debris disks physics, accessing disks with low enough optical depths that their structure is dominated by transport mechanisms rather than collisions. Hence, CGI will help us understand how exozodiacal dust grains are produced and transported in low-density disks around mature stars. Additionally, CGI will be able to measure the brightness level and constrain the degree of asymmetry of exozodiacal clouds around individual nearby sunlike stars in the optical, at the ~3x solar zodiacal emission level. This information will be extremely valuable for optimizing the observational strategy of possible future exo-Earth direct imaging missions, especially those planning to operate at optical wavelengths as well, such as the Habitable Exoplanet Observatory (HabEx) and the Large Ultraviolet/Optical/Infrared Surveyor (LUVOIR).

Demers, R.↗