The Most Predictive Physical Properties for the Stellar Population Radial Profiles of Nearby Galaxies

Abstract

We present a study on the radial profiles of the D4000, luminosity-weighted stellar ages τ L, and luminosity-weighted stellar metallicities [Z/H]L of 3654 nearby galaxies (0.01 < z < 0.15) using the IFU spectroscopic data from the MaNGA survey available in the SDSS DR15, in an effort to explore the connection between median stellar population radial gradients (i.e., ∇D4000, ∇τ L, ∇[Z/H]L) out to ∼1.5 R e and various galaxy properties, including stellar mass (M ⋆), specific star formation rate (sSFR), morphologies, and local environment. We find that M ⋆ is the single most predictive physical property for ∇D4000 and ∇[Z/H]L. The most predictive properties for ∇τ L are sSFR and, to a lesser degree, M ⋆. The environmental parameters, including local galaxy overdensities and central–satellite division, have virtually no correlation with stellar population radial profiles for the whole sample, but the ∇D4000 of star-forming satellite galaxies with M ⋆ ≲ 1010 M ⊙ exhibit a significant positive correlation with galaxy overdensities. Galaxies with lower sSFR have on average steeper negative stellar population gradients, and this sSFR dependence is stronger for more massive star-forming galaxies. The negative correlation between the median stellar population gradients and M ⋆ are best described largely as segmented relationships, whereby median gradients of galaxies with log M ⋆ ≲ 10.0 (with the exact value depending on sSFR) have much weaker mass dependence than galaxies with higher M ⋆. While the dependence of the radial gradients of ages and metallicities on T-Types and central stellar mass surface densities are generally not significant, galaxies with later T-Types or lower central mass densities tend to have significantly lower D4000, younger τ L, and lower [Z/H]L across the radial ranges probed in this study.

MaNGA galaxy properties -- I. An extensive optical, mid-infrared photometric, and environmental catalogue

“…However, the disagreement in our respective zero-points is significant and may result from our respective stellar mass calculations and different samples. Chen et al (2020a) used stellar masses provided by the NSA (Blanton et al 2011); our procedure is described in Section 2.2.4. Indeed, a large difference is found between the stellar masses by NSA and in this study; our photometry results in larger stellar masses by 0.34 (0.40) dex for LTGs (ETGs) that could be due to the systematic offsets of the MLCRs (see Figure 10).…”

“…We compare our LTG relation withWoo & Ellison (2019) andStone et al (2021), and our ETG relation withFang et al (2013) andBarro et al (2017) (see the text for the redshift range). Both panels show the Σ 1 − 𝑀 * relation ofChen et al (2020a) which fits all morphological types. A piece-wise linear fit to the DESI data is also shown for the ETGs (see the text for details).…”

Sub-galactic scaling relations with T$_{\rm e}$-based metallicity of low metallicity regions in galaxies: metal-poor gas inflow may have important effects?

“…Subsequently, we match the MaNGA Deep Learning DR15 Morphology catalog (DL; Domínguez to extract their morphological parameters, the T-Type value and the probability of merger, which have been widely used in previous works (e.g., Meert et al 2014;Fischer et al 2018;Chen et al 2020). This catalog is trained by Deep Learning algorithms using Convolutional Neural Networks based on the catalog of Nair & Abraham (2010) and color images.…”

Galaxy Zoo: 3D – crowdsourced bar, spiral, and foreground star masks for MaNGA target galaxies

“…For example, several works all using MaNGA data have looked at azimuthally averaged stellar population parameters (e.g. Li et al 2015;Ibarra-Medel et al 2016;Goddard et al 2017;Wang et al 2018;Chen et al 2019Chen et al , 2020Parikh et al 2021), or gas properties (e.g. Belfiore et al 2017Belfiore et al , 2018.…”

“…Many of these works (e.g. Goddard et al 2017;Wang et al 2018;Chen et al 2020;Parikh et al 2021) do comment on a difference in gradients linked to galaxy morphology (e.g. early-types tended to have flatter gradients than late-types), but in general they do not consider the systematics introduced into azimuthally averaged radial gradients by non-axisymmetric features such as bars, and spiral arms.…”