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arXiv · 2208.07511

Zwicky Transient Facility and Globular Clusters: Calibration of the gr-Band Absolute Magnitudes for the Yellow Post-Asymptotic-Giant-Branch Stars

Chow-Choong Ngeow·Anupam Bhardwaj·Daniel Reiley·Russ R. Laher·Josiah Purdum·Ben Rusholme
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Abstract

We present the first absolute calibration for the yellow post-asymptotic-giant-branch (PAGB) stars in the g- and r-band based on time-series observations from the Zwicky Transient Facility. These absolute magnitudes were calibrated using four yellow PAGB stars (one non-varying star and three Type II Cepheids) located in the globular clusters. We provide two calibrations of the gr-band absolute magnitudes for the yellow PAGB stars, by using an arithmetic mean and a linear regression. We demonstrate that the linear regression provides a better fit to the g-band absolute magnitudes for the yellow PAGB stars. These calibrated gr-band absolute magnitudes have a potential to be used as population II distance indicators in the era of time-domain synoptic sky surveys.

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Chow-Choong Ngeow, Anupam Bhardwaj, Daniel Reiley, Russ R. Laher, Josiah Purdum, Ben Rusholme. 2022-08-16. Zwicky Transient Facility and Globular Clusters: Calibration of the gr-Band Absolute Magnitudes for the Yellow Post-Asymptotic-Giant-Branch Stars. https://doi.org/10.3847/1538-3881%2Fac8a49

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