Bibcode
Cano-Díaz, M.; Sánchez, S. F.; Zibetti, S.; Ascasibar, Y.; Bland-Hawthorn, J.; Ziegler, B.; González Delgado, R. M.; Walcher, C. J.; García-Benito, R.; Mast, D.; Mendoza-Pérez, M. A.; Falcón-Barroso, J.; Galbany, L.; Husemann, B.; Kehrig, C.; Marino, R. A.; Sánchez-Blázquez, P.; López-Cobá, C.; López-Sánchez, Á. R.; Vilchez, J. M.
Bibliographical reference
The Astrophysical Journal Letters, Volume 821, Issue 2, article id. L26, pp. (2016).
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4
2016
Citations
171
Refereed citations
162
Description
The “main sequence of galaxies”—defined in terms of
the total star formation rate ψ versus the total stellar mass M
*—is a well-studied tight relation that has been
observed at several wavelengths and at different redshifts. All earlier
studies have derived this relation from integrated properties of
galaxies. We recover the same relation from an analysis of spatially
resolved properties, with integral field spectroscopic (IFS)
observations of 306 galaxies from the CALIFA survey. We consider the SFR
surface density in units of log(M ⊙ yr‑1
Kpc‑2) and the stellar mass surface density in units of
log(M ⊙ Kpc‑2) in individual spaxels
that probe spatial scales of 0.5–1.5 Kpc. This local relation
exhibits a high degree of correlation with small scatter (σ = 0.23
dex), irrespective of the dominant ionization source of the host galaxy
or its integrated stellar mass. We highlight (i) the integrated star
formation main sequence formed by galaxies whose dominant ionization
process is related to star formation, for which we find a slope of 0.81
± 0.02; (ii) for the spatially resolved relation obtained with
the spaxel analysis, we find a slope of 0.72 ± 0.04; and (iii)
for the integrated main sequence, we also identified a sequence formed
by galaxies that are dominated by an old stellar population, which we
have called the retired galaxies sequence.