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arXiv · 2103.15779

The InfraRed Imaging Spectrograph (IRIS) for TMT: photometric characterization of anisoplanatic PSFs and testing of PSF-Reconstruction via AIROPA

Nils Rundquist·Shelley A. Wright·Matthias Schoeck·Arun Surya·Jessica Lu·Paolo Turri·Edward L. Chapin·Eric Chisholm·Tuan Dod·Jennifer Dunn·Andrea Ghez·Yutaka Hayano·Chris Johnson·James E. Larkin·Reed L. Riddle·Ji Man Sohn·Ryuji Suzuki·Gregory Walth·Andrea Zonca
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Abstract

The InfraRed Imaging Spectrograph (IRIS) is a first-light instrument for the Thirty Meter Telescope (TMT) that will be used to sample the corrected adaptive optics field by the Narrow-Field Infrared Adaptive Optics System (NFIRAOS) with a near-infrared (0.8 - 2.4 $\mu$m) imaging camera and integral field spectrograph. To better understand IRIS science specifications we use the IRIS data simulator to characterize relative photometric precision and accuracy across the IRIS imaging camera 34"x34" field of view. Because the Point Spread Function (PSF) varies due to the effects of anisoplanatism, we use the Anisoplanatic and Instrumental Reconstruction of Off-axis PSFs for AO (AIROPA) software package to conduct photometric measurements on simulated frames using PSF-fitting as the PSF varies in single-source, binary, and crowded field use cases. We report photometric performance of the imaging camera as a function of the instrumental noise properties including dark current and read noise. Using the same methods, we conduct comparisons of photometric performance with reconstructed PSFs, in order to test the veracity of the current PSF-Reconstruction algorithms for IRIS/TMT.

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Nils Rundquist, Shelley A. Wright, Matthias Schoeck, Arun Surya, Jessica Lu, Paolo Turri, Edward L. Chapin, Eric Chisholm, Tuan Dod, Jennifer Dunn, Andrea Ghez, Yutaka Hayano, Chris Johnson, James E. Larkin, Reed L. Riddle, Ji Man Sohn, Ryuji Suzuki, Gregory Walth, Andrea Zonca. 2021-03-29. The InfraRed Imaging Spectrograph (IRIS) for TMT: photometric characterization of anisoplanatic PSFs and testing of PSF-Reconstruction via AIROPA. https://doi.org/10.1117/12.2562773

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