The Morphology of H{\alpha} emission in CALIFA galaxies

TL;DR

This study analyzes H-alpha emission profiles in 86 CALIFA galaxies, classifying their radial emission patterns and exploring their relation to galaxy types and evolutionary states.

Contribution

It introduces a two-step classification of H-alpha profiles and links these profiles to galaxy morphology and evolutionary indicators.

Findings

75% of galaxies have central H-alpha emission peaks

Elliptical and S0 galaxies mostly show central profiles

Spiral galaxies are mainly in extended or mixed profiles

Abstract

We have determined the H{\alpha} emission line radial profiles for a sample of 86 face-on galaxies observed in the CALIFA survey and analyzed with the Pipe3D pipeline. From a visual analysis we propose a two step classification of these profiles. Initially, they were divided in two classes with respect to the maximum of the H{\alpha} emission: C (for central) profiles have the maximum line emission at the galaxy center, whereas EX (for extended) profiles have the maximum H{\alpha} emission outside the galaxy center. After, we divided the C galaxies in two classes, CE and CL (where E and L stands here for 'early' and 'late'), through the value of $c_r$, the concentration index in the r-band. We analyzed the profile class dependence of several galaxy parameters, as well as examined the nature of line emission through the BPT diagram. We notice that almost 75% of the sample is in the C class. Elliptical and S0 galaxies dominate the CE class, with spiral galaxies being found mostly in the CL and EX classes. We also notice that spirals in each of these classes have different properties, with CL objects seeming less evolved than those in the EX class.