Searching for Planets in the Hyades IV: Differential Abundance Analysis of Hyades Dwarfs

نویسندگان

  • Diane B. Paulson
  • Christopher Sneden
  • William D. Cochran
چکیده

We present a differential abundance analysis of Hyades F-K dwarfs in search for evidence of stellar enrichment from accreted hydrogen deficient disk material. Metallicites and relative abundance ratios of several species have been determined. We derive a cluster mean [Fe/H] = 0.13±0.01. Two stars show abundances ∼0.2 dex larger than the cluster mean. Additionally, one star, which was added by a recent study as a cluster member, shows significantly lower abundances than the cluster mean. These three stars have questionable membership characteristics. The remaining stars in the survey have an rms of 0.04 dex in the differential [Fe/H] values. The Hyades cluster members have apparently not been significantly chemically enriched. The abundance ratios of Si, Ti, Na, Mg, Ca and Zn with respect to Fe are in their solar proportions. Subject headings: clusters: open (Hyades) — stars: abundances

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تاریخ انتشار 2003