Sulphur abundances from the S i near-infrared triplet at 1045 nm
E. CaffauGEPI, Observatoire de Paris, CNRS, Université Paris Diderot, Place Jules Janssen, 92190 Meudon, France e-mail: [email protected]R. FaraggianaUniversità degli Studi di Trieste, Dipartimento di Astronomia, Via Tiepolo 11, 34131 Trieste, ItalyP. BonifacioCIFIST Marie Curie Excellence TeamH.‐G. LudwigCIFIST Marie Curie Excellence TeamMatthias SteffenAstrophysikalisches Institut Potsdam, An der Sternwarte 16, 14482 Potsdam, Germany
2007en
ABI
Annotatsiya
Context.Unlike silicon and calcium, sulphur is an α-element that does not form dust. Some of the available observations of the evolution of sulphur with metallicity indicate an increased scatter of sulphur-to-iron ratios at low metallicities or even a bimodal distribution, with some stars showing constant S/Fe at all metallicities and others showing an increasing S/Fe ratio with decreasing metallicity. In metal-poor stars S i lines of Multiplet 1 at 920 nm are not yet too weak to permit the measurement of the sulphur abundance A(S); however, in ground-based observations they are severely affected by telluric lines.
Hali tarjima qilinmagan
Identifikatorlar
Iqtiboslar va manbalar
2 ta iqtibos0 ta foydalanilgan manba