Please use this identifier to cite or link to this item:
http://hdl.handle.net/20.500.12386/29097
Title: | AGN feedback and the origin of the α enhancement in early-type galaxies - insights from the GAEA model | Authors: | DE LUCIA, GABRIELLA FONTANOT, Fabio Hirschmann, Michaela |
Issue Date: | 2017 | Journal: | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | Number: | 466 | Issue: | 1 | First Page: | L88 | Abstract: | We take advantage of our recently published model for GAlaxy Evolution and Assembly (GAEA) to study the origin of the observed correlation between [α/Fe] and galaxy stellar mass. In particular, we analyse the role of radio-mode active galactic nuclei (AGN) feedback, which recent work has identified as a crucial ingredient to reproduce observations. In GAEA, this process introduces the observed trend of star formation histories extending over shorter time-scales for more massive galaxies, but does not provide a sufficient condition to reproduce the observed α enhancements of massive galaxies. In the framework of our model, this is possible only by assuming that any residual star formation is truncated for galaxies more massive than 10<SUP>10.5</SUP> M<SUB>☉</SUB>. This results, however, in even shorter star formation time-scales for the most massive galaxies, which translate in total stellar metallicities significantly lower than observed. Our results demonstrate that (I) trends of [α/Fe] ratios cannot be simply converted into relative time-scale indicators; and (II) AGN feedback cannot explain alone the positive correlation between [α/Fe] and galaxy mass/velocity dispersion. Reproducing simultaneously the mass-metallicity relation and the α enhancements observed pose a challenge for hierarchical models, unless more exotic solutions are adopted such as metal-rich winds or a variable initial mass function. | URI: | http://hdl.handle.net/20.500.12386/29097 | URL: | https://academic.oup.com/mnrasl/article/466/1/L88/2638361 | ISSN: | 0035-8711 | DOI: | 10.1093/mnrasl/slw242 | Bibcode ADS: | 2017MNRAS.466L..88D | Fulltext: | open |
Appears in Collections: | 1.01 Articoli in rivista |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
1611.04597(1).pdf | postprint | 231.59 kB | Adobe PDF | View/Open |
slw242.pdf | Pdf editoriale | 397.55 kB | Adobe PDF | View/Open |
Page view(s)
4
checked on Jan 18, 2021
Download(s)
2
checked on Jan 18, 2021
Google ScholarTM
Check
Altmetric
Items in DSpace are published in Open Access, unless otherwise indicated.