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arXiv · 1810.05736

The integrated properties of the CALIFA galaxies: Model-derived galaxy parameters and quenching of star formation

T. Bitsakis·S. F. Sanchez·L. Ciesla·P. Bonfini·V. Charmandaris·B. Cervantes Sodi·A. Maragkoudakis·T. Diaz-Santos·A. Zezas
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Abstract

We present a study of the integrated properties of the 835 galaxies in the CALIFA survey. To derive the main physical parameters of the galaxies we have fitted their UV-to-IR spectral energy distributions (SED) with sets of theoretical models using CIGALE. We perform a comparison of the integrated galaxy parameters derived from multi-band SED fitting with those obtained from modelling the Integral Field Unit (IFU) spectra and show the clear advantage of using the SED-derived star formation rates (SFR). A detailed analysis of galaxies in the SFR/Mstar plane as a function of their properties reveals that quenching of star formation is caused by a combination of gas deficiency and the inefficiency of the existing gas to form new stars. Exploring the plausible mechanisms that could produce this effect, we find a strong correlation with galaxy morphology and the build-up of central bulge. On the other hand, the presence of AGN and/or a stellar bar, as well as the local environment have only temporal effects on the current star formation, a result also consistent with their model-derived star formation histories.

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T. Bitsakis, S. F. Sanchez, L. Ciesla, P. Bonfini, V. Charmandaris, B. Cervantes Sodi, A. Maragkoudakis, T. Diaz-Santos, A. Zezas. 2018-10-12. The integrated properties of the CALIFA galaxies: Model-derived galaxy parameters and quenching of star formation. https://doi.org/10.1093/mnras%2Fsty2857

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