More insights into bar quenching. Multi-wavelength analysis of four barred galaxies

TL;DR

This study uses multi-wavelength data to analyze how stellar bars influence star formation quenching in four barred galaxies, revealing gas redistribution and depletion in the bar regions.

Contribution

It provides new insights into the role of stellar bars in gas redistribution and star formation suppression in barred galaxies through detailed multi-wavelength analysis.

Findings

Bar regions are depleted of neutral and molecular hydrogen in three galaxies.

Molecular hydrogen is abundant in the nuclear regions of all four galaxies.

Star formation is absent in the bar co-rotation radius in three out of four galaxies.

Abstract

The underlying nature of the process of star formation quenching in the central regions of barred disc galaxies that is due to the action of stellar bar is not fully understood. We present a multi-wavelength study of four barred galaxies using the archival data from optical, ultraviolet, infrared, CO, and HI imaging data on star formation progression and stellar and gas distribution to better understand the process of bar quenching. We found that for three galaxies, the region between the nuclear or central sub-kiloparsec region and the end of the bar (bar region) is devoid of neutral and molecular hydrogen. While the detected neutral hydrogen is very negligible, we note that molecular hydrogen is present abundantly in the nuclear or central sub-kiloparsec regions of all four galaxies. The bar co-rotation radius is also devoid of recent star formation for three out of four galaxies. One galaxy shows significant molecular hydrogen along the bar, which might mean that the gas is still being funnelled to the centre by the action of the stellar bar. Significant star formation is also present along the bar co-rotation radius of this galaxy. The study presented here supports a scenario in which gas redistribution as a result of the action of stellar bar clears the bar region of fuel for further star formation and eventually leads to star formation quenching in the bar region.