Properties of galaxies with an offset between the position angles of the major kinematic and photometric axes

TL;DR

This study investigates 18 galaxies with large offsets between their kinematic and photometric axes, finding no consistent distinctive features, implying diverse origins or influences for the observed offset.

Contribution

It provides a detailed analysis of galaxies with large axis offsets, revealing their properties are similar to those with small offsets, challenging assumptions about common origins.

Findings

No unique characteristics found in galaxies with large dPA.

Velocity fields show diverse morphologies.

Properties are similar to galaxies with small dPA.

Abstract

We derive the photometric, kinematic, and abundance characteristics of 18 star-forming MaNGA galaxies with fairly regular velocity fields and surface brightness distributions and with a large offset between the measured position angles of the major kinematic and photometric axes, dPA > 20 degree. The aim is to examine if there is any other distinctive characteristic common to these galaxies. We found morphological signs of interaction in some (in 11 out of 18) but not in all galaxies. The observed velocity fields show a large variety; the maps of the isovelocities vary from an hourglass-like appearance to a set of straight lines. The position angles of the major kinematic axes of the stellar and gas rotations are close to each other. The values of the central oxygen abundance, radial abundance gradient, and star formation rate are distributed within the intervals defined by galaxies with small (no) dPA of similar mass. Thus, we do not find any specific characteristic common to all galaxies with large dPA. Instead, the properties of these galaxies are similar to those of galaxies with small (no) dPA. This suggests that either the reason responsible for the large dPA does not influence other characteristics or the galaxies with large dPA do not share a common origin, they can, instead, originate through different channels.