Iron and <i>s</i>-elements abundance variations in NGC 5286: comparison with 'anomalous' globular clusters and Milky Way satellites

Simple item page
dc.contributor.authorMarino, A. F.
dc.contributor.authorMilone, A. P.
dc.contributor.authorKarakas, A. I.
dc.contributor.authorCasagrande, L.
dc.contributor.authorYong, D.
dc.contributor.authorShingles, L.
dc.contributor.authorDa Costa, G.
dc.contributor.authorNorris, J. E.
dc.contributor.authorStetson, P. B.
dc.contributor.authorLind, K.
dc.contributor.authorAsplund, M.
dc.contributor.authorCollet, R.
dc.contributor.authorJerjen, H.
dc.contributor.authorSbordone, L.
dc.contributor.authorAparicio, A.
dc.contributor.authorCassisi, S.
dc.date.accessioned2025-01-23T21:36:17Z
dc.date.available2025-01-23T21:36:17Z
dc.date.issued2015
dc.description.abstractWe present a high-resolution spectroscopic analysis of 62 red giants in the Milky Way globular cluster (GC) NGC 5286. We have determined abundances of representative light proton-capture, a, Fe-peak and neutron-capture element groups, and combined them with photometry of multiple sequences observed along the colour-magnitude diagram. Our principal results are: (i) a broad, bimodal distribution in s-process element abundance ratios, with two main groups, the s-poor and s-rich groups; (ii) substantial star-to-star Fe variations, with the s-rich stars having higher Fe, e.g. <[Fe/H]>(s-rich) - <[Fe/H]>(s-poor) similar to 0.2 dex; and (iii) the presence of O-Na-Al (anti) correlations in both stellar groups. We have defined a new photometric index, c(BVI) = (B - V) -(V - I), to maximize the separation in the colour-magnitude diagram between the two stellar groups with different Fe and s-element content, and this index is not significantly affected by variations in light elements (such as the O-Na anticorrelation). The variations in the overall metallicity present in NGC 5286 add this object to the class of anomalous GCs. Furthermore, the chemical abundance pattern of NGC 5286 resembles that observed in some of the anomalous GCs, e.g. M 22, NGC 1851, M 2, and the more extreme omega Centauri, that also show internal variations in s-elements, and in light elements within stars with different Fe and s-elements content. In view of the common variations in s-elements, we propose the term s-Fe-anomalous GCs to describe this sub-class of objects. The similarities in chemical abundance ratios between these objects strongly suggest similar formation and evolution histories, possibly associated with an origin in tidally disrupted dwarf satellites.
dc.fuente.origenWOS
dc.identifier.doi10.1093/mnras/stv420
dc.identifier.eissn1365-2966
dc.identifier.issn0035-8711
dc.identifier.urihttps://doi.org/10.1093/mnras/stv420
dc.identifier.urihttps://repositorio.uc.cl/handle/11534/101561
dc.identifier.wosidWOS:000356311600057
dc.issue.numero1
dc.language.isoen
dc.pagina.final845
dc.pagina.inicio815
dc.revistaMonthly notices of the royal astronomical society
dc.rightsacceso restringido
dc.subjectstars: abundances
dc.subjectglobular clusters: general
dc.subjectglobular clusters: individual: NGC 5286
dc.titleIron and <i>s</i>-elements abundance variations in NGC 5286: comparison with 'anomalous' globular clusters and Milky Way satellites
dc.typeartículo
dc.volumen450
sipa.indexWOS
sipa.trazabilidadWOS;2025-01-12
Files
Collections
Artículos de revistas