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Monthly Notices of the Royal Astronomical Society, vol.537, no.4, pp.3054-3065, 2025 (SCI-Expanded)
Understanding the evolution of metallic-line ( A m ) stars requires well-determined atmospheric parameters and abundance patterns of the selected candidates. In this study, we present a detailed abundance analysis of 15 Vul (HD 189849), identified as a marginal A m star, using a combination of equi v alent width and spectrum synthesis techniques, under the local thermodynamic equilibrium assumption. We compare our findings with previous analyses of the star, providing critique on both their results and our own. Our results suggest that, although 15 Vul exhibits some underabundances of calcium and scandium, which are typically associated with A m stars, it might more accurately be identified as a normal A star in terms of its abundance pattern of all other elements and microturbulence velocity. The stars position on the Hertzsprung-Russell diagram, along with our findings, may indicate that it is potentially a classical A m star that has evolved into the subgiant phase as a quasi-normal star. This may be the first identification of an evolved A m star.