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arXiv · 1210.6300

The [Fe/H] Dependence on the Ca {\sc ii}-$M_V$ Relationship

Thomas Gomez·George Wallerstein·Elena Pancino
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Abstract

We examined the Wilson-Bappu effect, a relationship between the absolute magnitude of the star, $M_V$, and the logarithm of the Ca {\sc ii} emission width, $W_0$, over the largest $M_V$ range to date, +13 to -5, covering M-dwarfs to type Ia supergiants. We used an extensive literature, the latest Hipparcos reduction, data from two globular clusters, and new observations from Apache Point Observatory to compile a sample that allowed us to study the effect of [Fe/H] on the Wilson-Bappu relationship. Our results include reporting the deviations from linearity and demonstrating that the Wilson-Bappu relationship is insensitive to metallicity.

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Thomas Gomez, George Wallerstein, Elena Pancino. 2012-10-23. The [Fe/H] Dependence on the Ca {\sc ii}-$M_V$ Relationship. https://doi.org/10.1086/668845

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