The MUSE Atlas of Disks (MAD): resolving star formation rates and gas metallicities on <100 pc scales†

Abstract

We study the physical properties of the ionized gas in local disks using the sample of 38 nearby ∼ 10 8.5−11.2 M Star-Forming Main Sequence (SFMS) galaxies observed so far as part of the MUSE Atlas of Disks (MAD). Specifically, we use all strong emission lines in the MUSE wavelength range 4650-9300Å to investigate the resolved ionized gas properties on ∼ 100 pc scales. This spatial resolution enables us to disentangle Hii regions from the Diffuse Ionized Gas (DIG) in the computation of gas metallicities and Star Formation Rates (SFRs) of star forming regions.The gas metallicities generally decrease with radius. The metallicity of the Hii regions is on average ∼0.1 dex higher than that of the DIG, but the metallicity radial gradient in both components is similar. The mean metallicities within the inner galaxy cores correlate with the total stellar mass of the galaxies. On our < 100 pc scales, we find two correlations previously reported at kpc scales: a spatially resolved Mass-Metallicity Relation (RMZR) and a spatially resolved SFMS (RSFMS). We find no secondary dependency of the RMZR with the SFR density. We find that both resolved relations have a local origin, as they do not depend on the total stellar mass. The observational results of this paper are consistent with the inside-out scenario for the growth of galactic disks.

Variations in the slope of the resolved star-forming main sequence: a tool for constraining the mass of star-forming regions

“…In recent years, various authors have studied the spatially resolved SFR-stellar mass relation (rSFMS) using photometric or integral field unit (IFU) observations of individ-ual galaxies (e.g. Cano-Díaz et al 2016;González Delgado et al 2016;Abdurro'uf & Akiyama 2017;Hsieh et al 2017;Maragkoudakis et al 2017;Ellison et al 2018;Liu et al 2018;Erroz-Ferrer et al 2019). While the observed rSFMS on ∼kpc and 100 pc scales has been documented by recent observational surveys, the correlation between the resolved stellar mass surface density (Σ ) and SFR surface density (Σ SFR ) has not been explored in depth in numerical simulations.…”

Resolved scaling relations and metallicity gradients on sub-kiloparsec scales at z ≈ 1

“…It has even been argued that these three properties are connected by a single plane, the fundamental mass-metallicity relation (Lara-López et al 2010;Mannucci et al 2010), that does not evolve with redshift, although its existence is still controversial (e.g. Sánchez et al 2013;Erroz-Ferrer et al 2019). These scaling relations are well explained by "reservoir" models.…”

“…CALIFA Sánchez et al 2014, MaNGA Bundy et al 2015, SAMI Croom et al 2012and MAD Erroz-Ferrer et al 2019, it has also been established that both the Star-Forming Main Sequence and the Mass-Metallicity Relation exist on sub-galactic scales (e.g. Sánchez et al 2013;Erroz-Ferrer et al 2019). Moreover, it has been argued that these resolved relations are in fact more fundamental than the integrated ones (Rosales-Ortega et al 2012;Barrera-Ballesteros et al 2016), i.e., that the galaxy wide scalingrelations are a consequence of the local relations between stellar mass surface density, star-formation surface density and metallicity.…”

Milky Way analogues in MaNGA: multiparameter homogeneity and comparison to the Milky Way

“…Our understanding of resolved galaxy properties has significantly improved in more recent years in large part due to the advent of large sample, integral field unit (IFU) spectroscopic surveys, such as ATLAS3D (Cappellari et al 2011), CALIFA (Sánchez et al 2012a), SAMI (Croom et al 2012), MAD (Erroz-Ferrer et al 2019), andMaNGA (Bundy et al 2015). Quiescent galaxies show a range of kinematic behaviours, with some being dispersion-dominated and others retaining a significant level of rotational support (e.g.…”