Requirements and design reference mission for the WFIRST/AFTA coronagraph instrument

16 September 2015 Requirements and design reference mission for the WFIRST/AFTA coronagraph instrument

Proceedings Volume 9605, Techniques and Instrumentation for Detection of Exoplanets VII; 960502 (2015) https://doi.org/10.1117/12.2191792
Event: SPIE Optical Engineering + Applications, 2015, San Diego, California, United States

Abstract

The WFIRST-AFTA coronagraph instrument takes advantage of AFTAs 2.4-meter aperture to provide novel exoplanet imaging science at approximately the same instrument cost as an Explorer mission. The AFTA coronagraph also matures direct imaging technologies to high TRL for an Exo-Earth Imager in the next decade. The coronagraph Design Reference Mission (DRM) optical design is based on the highly successful High Contrast Imaging Testbed (HCIT), with modifications to accommodate the AFTA telescope design, service-ability, volume constraints, and the addition of an Integral Field Spectrograph (IFS). In order to optimally satisfy the three science objectives of planet imaging, planet spectral characterization and dust debris imaging, the coronagraph is designed to operate in two different modes: Hybrid Lyot Coronagraph or Shaped Pupil Coronagraph. Active mechanisms change pupil masks, focal plane masks, Lyot masks, and bandpass filters to shift between modes. A single optical beam train can thus operate alternatively as two different coronagraph architectures. Structural Thermal Optical Performance (STOP) analysis predicts the instrument contrast with the Low Order Wave Front Control loop closed. The STOP analysis was also used to verify that the optical/structural/thermal design provides the extreme stability required for planet characterization in the presence of thermal disturbances expected in a typical observing scenario. This paper describes the instrument design and the flow down from science requirements to high level engineering requirements.

Citation Download Citation

Richard T. Demers, Frank Dekens, Rob Calvet, Zensheu Chang, Robert Effinger, Eric Ek, Larry Hovland, Laura Jones, Anthony Loc, Bijan Nemati, Charley Noecker, Timothy Neville, Hung Pham, Mike Rud, Hong Tang, and Juan Villalvazo "Requirements and design reference mission for the WFIRST/AFTA coronagraph instrument", Proc. SPIE 9605, Techniques and Instrumentation for Detection of Exoplanets VII, 960502 (16 September 2015); https://doi.org/10.1117/12.2191792

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available