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arXiv · 2207.03607

Absolute Flux Calibrations for the Nancy Grace Roman Space Telescope Coronagraph Instrument

Lindsey Payne·Robert T. Zellem·Marie Ygouf·Bruce Macintosh
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Abstract

The Nancy Grace Roman Space Telescope's (Roman) Coronagraph Instrument is a technology demonstration equipped to achieve flux contrast levels of up to 10$^{-9}$. This precision depends upon the quality of observations and their resultant on-sky corrections via an absolute flux calibration (AFC). Our plan utilizes 10 dim and 4 bright standard photometric calibrator stars from Hubble Space Telescope's (HST) CALSPEC catalog to yield a final AFC error of 1.94\% and total observation time of $\sim$22 minutes. Percent error accounts for systematic uncertainties (filters, upstream optics, quantum efficiency) in Roman component instrumentation along with shot noise for a signal to noise ratio (SNR) of 500.

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Lindsey Payne, Robert T. Zellem, Marie Ygouf, Bruce Macintosh. 2022-07-07. Absolute Flux Calibrations for the Nancy Grace Roman Space Telescope Coronagraph Instrument. https://arxiv.org/abs/2207.03607

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