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Understanding the detailed properties of stars in the infrared is of critical importance with new missions focusing on the infrared (JWST, Roman). The ground-based wide-field infrared instrument, FourStar, on the Magellan telescope contains a number of medium band filters that are optimized for photometric redshifts, but also provide nearly continuous spectral coverage for stars. These filters, however, lack absolute calibration. In this project, we adapted a technique used for galaxies to be used for stars. We used multi-band photometry to fit a likely SED model to each star and then generated synthetic photometry from the SED model to produce the magnitude of the star in a given filter. Statistically, we then determined the zero point in each filter in each image. This will be used to calibrate a large survey aiming to better understand near-infrared properties of stars for application to the extragalactic distance scale (with JWST and Roman).
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A Semi-Empirical Approach for Photometric Zeropoints Using Stars
Understanding the detailed properties of stars in the infrared is of critical importance with new missions focusing on the infrared (JWST, Roman). The ground-based wide-field infrared instrument, FourStar, on the Magellan telescope contains a number of medium band filters that are optimized for photometric redshifts, but also provide nearly continuous spectral coverage for stars. These filters, however, lack absolute calibration. In this project, we adapted a technique used for galaxies to be used for stars. We used multi-band photometry to fit a likely SED model to each star and then generated synthetic photometry from the SED model to produce the magnitude of the star in a given filter. Statistically, we then determined the zero point in each filter in each image. This will be used to calibrate a large survey aiming to better understand near-infrared properties of stars for application to the extragalactic distance scale (with JWST and Roman).
more »
« less
- PAR ID:
- 10654769
- Publisher / Repository:
- 245th Meeting of the American Astronomical Society, id. 353.23. Bulletin of the American Astronomical Society, Vol. 57, No. 2 e-id 2025n2i353 p23
- Date Published:
- Volume:
- 57
- Issue:
- 2
- Page Range / eLocation ID:
- 23
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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