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arXiv · 1702.01602

Spectrophotometry of Very Bright Stars in the Southern Sky

Kevin Krisciunas·Nicholas B. Suntzeff·Bethany Kelarek·Kyle Bonar·Joshua Stenzel
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Abstract

We obtained spectra of 26 bright stars in the southern sky, including Sirius, Canopus, Betelgeuse, Rigel, Bellatrix, and Procyon, using the 1.5-m telescope at Cerro Tololo Inter-American Observatory and its grating spectrograph RCSPEC. A 7.5 magnitude neutral density filter was used to keep from saturating the CCD. Our spectra are tied to a Kurucz model of Sirius with T = 9850 K, log g = 4.30, and [Fe/H] =+0.4. Since Sirius is much less problematic than using Vega as a fundamental calibrator, the synthetic photometry of our stars constitutes a Sirius-based system that could be used as a new anchor for stellar and extragalactic photometric measurements.

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Kevin Krisciunas, Nicholas B. Suntzeff, Bethany Kelarek, Kyle Bonar, Joshua Stenzel. 2017-02-19. Spectrophotometry of Very Bright Stars in the Southern Sky. https://doi.org/10.1088/1538-3873%2Faa5f0e

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