The Astrophysical Journal Supplement Series, Volume 227, Issue 2, article id. 24, 34 pp. (2016).
Kim, Hak-Sub; Cho, Jaeil; Sharples, Ray M.; Vazdekis, A.; Beasley, M. A.; Yoon, Suk-Jin
We perform integrated spectroscopy of 24 Galactic globular clusters (GGCs). Spectra are observed from one core radius for each cluster with a high wavelength resolution of ∼2.0 Å FWHM. In combination with two existing data sets from Puzia et al. and Schiavon et al., we construct a large database of Lick spectral indices for a total of 53 GGCs with a wide range of metallicities, ‑2.4 ≲ [Fe/H] ≲ 0.1, and various horizontal-branch morphologies. The empirical index-to-metallicity conversion relationships are provided for the 20 Lick indices for the use of deriving metallicities for remote, unresolved stellar systems.