Abstract

NASA’s Wide-Field Infrared Survey Telescope (WFIRST) is a space-based observatory now being designed for launch in the mid-2020s. As the U.S. astronomical community’s top-priority mission for this decade, WFIRST is designed not only as a “discovery machine” for general PI-driven science but also as a survey platform to address three fundamental problems at the forefront of modern astrophysics: the dark energy content of the Universe, the evolution of the high-redshift galaxy and quasar population, and the demographics of exoplanets in our own galaxy. WFIRST’s primary camera, the Wide-Field Instrument (WFI), is a near-IR imager under development by Ball Aerospace and NASA’s Goddard Space Flight Center that will provide a field of view over 100 times greater than that of the Hubble Space Telescope.

Achieving WFIRST’s key science objectives will require WFI to obtain imagery of faint galaxies, stars, and supernovae with unprecedented photometric precision. Attaining this level of accuracy demands calibrating the data at a level never previously accomplished in space. To meet these requirements, Ball Aerospace and Utah State University’s Space Dynamics Laboratory (SDL) are collaborating to design and build the Relative Calibration System (RCS) for WFI. The RCS is a self-calibrating unit which will generate temporally and spatially stable illumination of the WFI focal plane at a variety of wavelengths over an exceptionally large range of intensity. The RCS will enable not only standard tests of pixel-to-pixel sensitivity and gain from space, but also assessments of interpixel non-linearity, charge persistence, total-count-dependent non-linearity, and count-rate-dependent non-linearity throughout the mission’s lifetime. This talk will explore novel aspects of the RCS hardware design that permit the system to meet these demanding requirements.

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Jun 17th, 4:00 PM

The WFI Relative Calibration System for WFIRST

NASA’s Wide-Field Infrared Survey Telescope (WFIRST) is a space-based observatory now being designed for launch in the mid-2020s. As the U.S. astronomical community’s top-priority mission for this decade, WFIRST is designed not only as a “discovery machine” for general PI-driven science but also as a survey platform to address three fundamental problems at the forefront of modern astrophysics: the dark energy content of the Universe, the evolution of the high-redshift galaxy and quasar population, and the demographics of exoplanets in our own galaxy. WFIRST’s primary camera, the Wide-Field Instrument (WFI), is a near-IR imager under development by Ball Aerospace and NASA’s Goddard Space Flight Center that will provide a field of view over 100 times greater than that of the Hubble Space Telescope.

Achieving WFIRST’s key science objectives will require WFI to obtain imagery of faint galaxies, stars, and supernovae with unprecedented photometric precision. Attaining this level of accuracy demands calibrating the data at a level never previously accomplished in space. To meet these requirements, Ball Aerospace and Utah State University’s Space Dynamics Laboratory (SDL) are collaborating to design and build the Relative Calibration System (RCS) for WFI. The RCS is a self-calibrating unit which will generate temporally and spatially stable illumination of the WFI focal plane at a variety of wavelengths over an exceptionally large range of intensity. The RCS will enable not only standard tests of pixel-to-pixel sensitivity and gain from space, but also assessments of interpixel non-linearity, charge persistence, total-count-dependent non-linearity, and count-rate-dependent non-linearity throughout the mission’s lifetime. This talk will explore novel aspects of the RCS hardware design that permit the system to meet these demanding requirements.