Abundance ratios in dwarf elliptical galaxies

We determine abundance ratios of 37 dwarf ellipticals (dEs) in the nearby Virgo cluster. This sample is representative of the early-type population of galaxies in the absolute magnitude range -19.0 < Mr < -16.0. We analyze their absorption line-strength indices by means of index-index diagrams...

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Bibliographische Detailangaben
Hauptverfasser: Şen, Şeyda (VerfasserIn) , Lisker, Thorsten (VerfasserIn)
Dokumenttyp: Article (Journal) Kapitel/Artikel
Sprache:Englisch
Veröffentlicht: 18 Dec 2017
Ausgabe:Version V2
In: Arxiv
Year: 2017, Pages: 1-15
DOI:10.48550/arXiv.1712.04953
Online-Zugang:Resolving-System, kostenfrei, Volltext: https://doi.org/10.48550/arXiv.1712.04953
Verlag, kostenfrei, Volltext: http://arxiv.org/abs/1712.04953
Volltext
Verfasserangaben:Ş Şen, R.F. Peletier, A. Boselli, M. den Brok, J. Falcón-Barroso, G. Hensler, J. Janz, E. Laurikainen, T. Lisker, J.J. Mentz, S. Paudel, H. Salo, A. Sybilska, E. Toloba, G. van de Ven, A. Vazdekis and C. Yesilyaprak
Beschreibung
Zusammenfassung:We determine abundance ratios of 37 dwarf ellipticals (dEs) in the nearby Virgo cluster. This sample is representative of the early-type population of galaxies in the absolute magnitude range -19.0 < Mr < -16.0. We analyze their absorption line-strength indices by means of index-index diagrams and scaling relations and use the stellar population models to interpret them. We present ages, metallicities and abundance ratios obtained from these dEs within an aperture size of Re/8. We calculate [Na/Fe] from NaD, [Ca/Fe] from Ca4227 and [Mg/Fe] from Mgb. We find that [Na/Fe] is under-abundant with respect to solar while [Mg/Fe] is around solar. This is exactly opposite to what is found for giant ellipticals, but follows the trend with metallicity found previously for the Fornax dwarf NGC 1396. We discuss possible formation scenarios that can result in such elemental abundance patterns and we speculate that dEs have disk-like SFH favouring them to originate from late-type dwarfs or small spirals. Na-yields appear to be very metal-dependent, in agreement with studies of giant ellipticals, probably due to the large dependence on the neutron-excess in stars. We conclude that dEs have undergone a considerable amount of chemical evolution, they are therefore not uniformly old, but have extended SFH, similar to many of the Local Group galaxies.
Beschreibung:V1 13. Dezember 2017, V2 18. Dezember 2017
Gesehen am 16.03.2018
Beschreibung:Online Resource
DOI:10.48550/arXiv.1712.04953