Scaling Relations across Galaxy Classification Schemes: I. Star Formation Rate-Stellar Mass Plane of CALIFA Nearby Galaxies

TL;DR

This study explores how galaxy morphology, gravitational potential, and star formation activity interrelate by analyzing the star formation rate-stellar mass relation across different galaxy classifications in the CALIFA survey.

Contribution

It introduces a multi-faceted classification approach combining structural, gravitational, and quenching indicators to better understand galaxy evolution and star formation suppression.

Findings

Clear separation of galaxy populations on the star formation rate-stellar mass plane.

Different galaxy types occupy distinct regions correlating with their morphology and gravitational potential.

Morphological groups show unique star formation and quenching characteristics.

Abstract

To gain deeper insights into galaxy evolution and the mechanisms driving transitions between different galaxy morphologies, we analyse the connection between star formation rate and stellar mass for 231 galaxies spanning Hubble types E1-Sdm from the Calar Alto Legacy Integral Field Spectroscopy Area survey using three complementary classification schemes. The Hubble classification provides structural information, the circular velocity curve classification$-$based on principal component analysis$-$ traces the total gravitational potential, and the Quenching classification$-$derived from H$_{\alpha}$ equivalent width maps$-$indicates the spatial extent of quenched regions relative to star-forming areas. We find a clear separation of galaxy populations on the star formation rate-stellar mass plane. Late-type spirals with slow-rising circular velocity curves, represented by star-forming and quiescent-nuclear-ring galaxies, dominate the blue cloud. Early-type spirals with flat or round-peaked circular velocity curves belonging to centrally quiescent or mixed class populate the green valley, representing a transitional stage. Elliptical and lenticular galaxies with round- or sharp-peaked circular velocity curves from nearly retired or fully retired QSs reside on the red sequence. Furthermore, our results indicate that the morphological groups Sc-Scd, Sd-Sdm, and E1-E3 are characterized by a unique set of QSs and circular velocity curves, while galaxies with morphologies such as Sa-Sbc spread over multiple QSs and circular velocity curves. The distribution of the classification classes shows a tight link between galaxy structure, gravitational potential, and suppression of star-formation in the galaxies.