Cluster dwarfs galaxies and the [\alpha/Fe]-mass relation

Romero-Gómez, J.; Peletier, Reynier F.; Aguerri, J. A. L.
Bibliographical reference

Highlights of Spanish Astrophysics XI

Advertised on:
5
2023
Number of authors
3
IAC number of authors
2
Citations
0
Refereed citations
0
Description
Using spectral data from the SAMI Integral Field Spectrograph and full spectral fitting techniques, we obtain and study the stellar population properties of a sample of dwarf galaxies in the Fornax Cluster. Our analysis focuses on the relation of stellar populations properties with the environment and internal properties of dwarfs. We covered the stellar mass range from $10^{4}$ to $10^{12} M_{\odot}$ by adding massive galaxies from the ATLAS$^{3D}$ project and satellite galaxies of the Milky Way. Using the whole sample we find that the mass-metallicity relation is not linear and that the [$\alpha$/Fe]-stellar mass relation shows a U-shape, with a minimum in [$\alpha$/Fe] for masses between $10^{9}-10^{10} M_{\odot}$. In addition to the [$\alpha$/Fe]-stellar mass relation, we find that the [$\alpha$/Fe] of dwarfs also relates with clustercentric distance in nearby clusters and in the the Milky Way. This shows that when the faintest galaxies fall to the environment a rapid burst of star formation is induced, leading to high [$\alpha$/Fe] values. Then different quenching mechanisms blow the gas content away. More massive galaxies are barely affected by the environment, maintaining their gas and producing several bursts of star formation, thus, regulating their stellar populations by internal processes, leading to [$\alpha$/Fe] increasing with mass.