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arXiv · 1406.4883

BVI Photometry and the Red Giant Branch Luminosity Function of M15

Diane K. Feuillet·Nathaniel E. Q. Paust·Brian Chaboyer
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Abstract

We present new $BVI$ photometry containing 40,000 stars of the Galactic globular cluster M15 (NGC 7078) covering a $25 \times 25$ arcminute area centered on the cluster with a magnitude range from the tip of the Red Giant Branch to three magnitudes below the main sequence turn-off. Using $α$-enhanced Dartmouth Stellar Evolution Program models, we find an age of $13.0 \ \pm \ 1.0$ Gyr and distance modulus of $(m-M)_V = 15.4 \pm 0.1$ through isochrone fitting. Unlike previous works, we find good agreement between the observed completeness-corrected stellar luminosity function and models.

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Diane K. Feuillet, Nathaniel E. Q. Paust, Brian Chaboyer. 2014-06-18. BVI Photometry and the Red Giant Branch Luminosity Function of M15. https://doi.org/10.1086/677845

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