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تسجيل مستخدم جديدDetailed abundance analysis of 8 super-metal-rich star candidates
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We provide detailed abundance analyses of 8 candidate super-metal-rich stars. Five of them are confirmed to have [Fe/H] > 0.2 dex, the generally-accepted limit for super-metal-richness. Furthermore, we derive abundances of several elements and find that the stars follow trends seen in previous studies of metal-rich stars. Ages are estimated from isochrones and velocities calculated. We find that there do exist very metal-rich stars that are older than 10 Gyr. This is contrary to what is found in several recent studies of the galactic age-metallicity relation. This is tentative evidence that there might not exist a one-to-one relation between age and metallicity for all stars. This is not surprising considering the current models of the independent evolution of the different galactic components. We also find that one star, HD 182572, could with ~ 75 % chance be a thick disk star with, for the thick disk, an extremely high metallicity at 0.34 dex. This star is, intriguingly, also somewhat enhanced in the alpha-elements.
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