Elemental Abundances of Three Red Giants in Terzan 7, a Globular Cluster Associated with the Sagittarius Galaxy

Chemical abundances in three giants in Terzan 7, a globular cluster associated with the Sagittarius dwarf galaxy, have been determined using high-resolution spectra obtained with the UVES spectrograph on the ESO 8.2 m Kueyen telescope. We find the overall metallicity of the stars to be [Fe/H]= -0.61 ± 0.07, which is slightly higher than that previously evaluated from photometry and used for the age determination of this cluster. This metallicity yields an age of about 6 Gyr, which is slightly lower than derived from previous estimates. The relative abundance ratios of various chemical elements to iron lie between those of its host galaxy's metal-poor and metal-rich stars and reveal an intriguing similarity to the pattern seen in the Large Magellanic Cloud.

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