SDSS-IV MaNGA: effects of morphology in the global and local star formation main sequences

Abstract

We study the global star-formation rate (SFR) vs. stellar mass (M * ) correlation, and the spatially-resolved SFR surface density (Σ S FR ) vs. stellar mass surface density (Σ * ) correlation, in a sample of ∼ 2, 000 galaxies from the MaNGA MPL-5 survey. We classify galaxies and spatially-resolved areas into star-forming and retired according to their ionization processes. We confirm the existence of a Star-Forming Main Sequence (SFMS) for galaxies and spatially-resolved areas, and show that they have the same nature, with the global as a consequence of the local one. The latter presents a bend below a limit Σ * value, ≈ 3 × 10 7 M ⊙ kpc −2 , which is not physical. Using only star-forming areas (SFAs) above this limit, a slope and a scatter of ≈ 1 and ≈ 0.27 dex are determined. The retired galaxies/areas strongly segregate from their respective SFMS's, by ∼ −1.5 dex on average. We explore how the global/local SFMS's depend on galaxy morphology, finding that for star-forming galaxies and SFAs, there is a trend to lower values of star-formation activity with earlier morphological types, which is more pronounced for the local SFMS. The morphology not only affects the global SFR due to the diminish of SFAs with earlier types, but also affects the local SF process. Our results suggest that the local SF at all radii is established by some universal mechanism partially modulated by morphology. Morphology seems to be connected to the slow aging and sharp decline of the SF process, and on its own it may depend on other properties as the environment.

J-PLUS: The star formation main sequence and rate density at d ≲ 75 Mpc

“…As a final remark, the star-forming and post-AGB ionized sources produce also two different populations in the spatiallyresolved SFMS (e.g. Hsieh et al 2017;Cano-Díaz et al 2019). The J-PLUS DR1 sample analyzed in this paper is well suited for spatially-resolved studies, providing extra clues about the origin of the measured Hα flux.…”

A panchromatic spatially resolved analysis of nearby galaxies – I. Sub-kpc-scale main sequence in grand-design spirals

“…Rodighiero et al 2014). In this Section, we thus compare our panchromatic results with the spatially resolved MS relations obtained with data from CALIFA (Cano-Díaz et al 2016), MaNGA (Hsieh et al 2017;Cano-Díaz et al 2019;Bluck et al 2019), and SAMI (Medling et al 2018). For completeness, we also compare our results with the MS relations of Abdurro'uf & Akiyama (2017), that perform pixel-bypixel SED fitting to GALEX and SDSS photometry of local (0.01 < z < 0.02) massive spiral galaxies selected in the MPI-JHU (Max Planck Institute for Astrophysics-Johns Hopkins University), and of Hall et al (2018), obtained for a sample of 355 nearby galaxies, with spatially resolved observations of Hα and mid-IR emission.…”

“…Indeed, there are indication that galaxy morphology plays an important role in the characterising the spatially resolved MS relation, especially its scatter (e.g. González Delgado et al 2016;Cano-Díaz et al 2019). Maragkoudakis et al (2017) observe a decrease in the spatially resolved MS relation from late-type to early-type spirals, while the scatter remains constant.…”

“…4.2) that usually span the range 0.7 − 1.1 despite using different SFR tracers and different redshift and stellar mass ranges for the analysis (i.e. Pérez et al 2013;Wuyts et al 2013;Hemmati et al 2014;Cano-Díaz et al 2016;González Delgado et al 2016;Abdurro'uf & Akiyama 2017;Abdurro'uf 2018;Hall et al 2018;Cano-Díaz et al 2019). It is worth noting that several of the literature works implement the orthogonal distance regression (ODR) method to find the location of the MS relation.…”

“…Thus, they conclude that the MS scatter can be driven by systematic differences in the star formation process among galaxies or their global environment. Cano-Díaz et al (2019) exploited a sample of 2000 MaNGA galaxies to study the global and spatially resolved MS and its dependence on morphology. They find a spatially resolved MS with a slope close to 1 and a scatter of 0.27 dex, around which SF areas are located depending on the galaxy integrated morphology.…”