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arXiv · 2206.01852

Evaluating the V-band Photometric Metallicity with Fundamental Mode RR Lyrae in the Kepler Field

Chow-Choong Ngeow
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Abstract

The aim of this work is to evaluate the performance of photometric metallicity [Fe/H], determined based on V-band light-curves photometrically transformed from the gr-band light-curves. We tested this by using a set of homogeneous sample of fundamental mode RR Lyrae located in the Kepler field. It was found that the color-term is necessary in such photometric transformation. We demonstrated that including the color-term the determined photometric [Fe/H] are in good agreement to the spectroscopic [Fe/H], either based on the calibrated or the transformed V-band light-curves. We also tested the impact of Blazhko RR Lyrae in determining the photometric Fe/H], and found that Blazhko RR Lyrae can give consistent photometric [Fe/H]. Finally, we derived independent gVr-band [Fe/H]-$\phi_{31}$-P relations (where $\phi_{31}$ and P are Fourier parameter and pulsation period, respectively) using our light-curves. The V-band relation is in good agreement with the most recent determination given in the literature.

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Chow-Choong Ngeow. 2022-06-03. Evaluating the V-band Photometric Metallicity with Fundamental Mode RR Lyrae in the Kepler Field. https://doi.org/10.3847/1538-3881%2Fac75ec

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