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arXiv · 2209.03348

The JWST Resolved Stellar Populations Early Release Science Program I.: NIRCam Flux Calibration

Martha L. Boyer·Jay Anderson·Mario Gennaro·Marla Geha·Kristen B. Wingfield McQuinn·Erik Tollerud·Matteo Correnti·Max J. Brenner Newman·Roger E. Cohen·Nitya Kallivayalil·Rachel Beaton·Andrew A. Cole·Andrew Dolphin·Jason S. Kalirai·Karin M. Sandstrom·Alessandro Savino·Evan D. Skillman·Daniel R. Weisz·Benjamin F. Williams
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Abstract

We use globular cluster data from the Resolved Stellar Populations Early Release Science (ERS) program to validate the flux calibration for the Near Infrared Camera (NIRCam) on the James Webb Space Telescope (JWST). We find a significant flux offset between the eight short wavelength detectors, ranging from 1-23% (about 0.01-0.2 mag) that affects all NIRCam imaging observations. We deliver improved zeropoints for the ERS filters and show that alternate zeropoints derived by the community also improve the calibration significantly. We also find that the detector offsets appear to be time variable by up to at least 0.1 mag.

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Martha L. Boyer, Jay Anderson, Mario Gennaro, Marla Geha, Kristen B. Wingfield McQuinn, Erik Tollerud, Matteo Correnti, Max J. Brenner Newman, Roger E. Cohen, Nitya Kallivayalil, Rachel Beaton, Andrew A. Cole, Andrew Dolphin, Jason S. Kalirai, Karin M. Sandstrom, Alessandro Savino, Evan D. Skillman, Daniel R. Weisz, Benjamin F. Williams. 2022-09-06. The JWST Resolved Stellar Populations Early Release Science Program I.: NIRCam Flux Calibration. https://arxiv.org/abs/2209.03348

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