The Abundance Properties of Nearby Late-Type Galaxies. \\ II. The Relation between Abundance Distributions and Surface Brightness Profiles

TL;DR

This study investigates how oxygen abundance correlates with surface brightness in late-type galaxies, revealing that the relation depends on galactocentric distance and galaxy properties, and proposing a parametric model for better accuracy.

Contribution

It introduces a parametric OH-SB relation that accounts for galactocentric distance, disk scale length, and T-type, improving the modeling of abundance distributions in galaxies.

Findings

The OH-SB relation varies with galactocentric distance and galaxy properties.

A parametric relation reduces deviations by ~1.4 times compared to a simple model.

The relation's dependence on parameters differs between galaxy centers and edges.

Abstract

The relations between oxygen abundance and disk surface brightness (OH-SB relation) in the infrared W1 band are examined for a nearby late-type galaxies. The oxygen abundances were presented in Paper I. The photometric characteristics of the disks are inferred here using photometric maps from the literature through bulge-disk decomposition. We find evidence that the OH - SB relation is not unique but depends on the galactocentric distance r (taken as a fraction of the optical radius R_25) and on the properties of a galaxy: the disk scale length h and the morphological T-type. The parametric OH - SB relation reproduces the observed data better than a simple, one-parameter relation; the deviations resulting when using our parametric relation are smaller by a factor of ~1.4 than that the simple relation. The influence of the parameters on the OH - SB relation varies with galactocentric distance. The influence of the T-type on the OH - SB relation is negligible at the centers of galaxies and increases with galactocentric distance. In contrast, the influence of the disk scale length on the OH -- SB relation is maximum at the centers of galaxies and decreases with galactocentric distance, disappearing at the optical edges of galaxies. Two-dimensional relations can be used to reproduce the observed data at the optical edges of the disks and at the centers of the disks. The disk scale length should be used as a second parameter in the OH - SB relation at the center of the disk while the morphological T-type should be used as a second parameter in the relation at optical edge of the disk. The general properties of the abundance - surface brightness relations are similar for the three considered bands B, K, and W1.