Testing a theoretical prediction for bar formation in galaxies with bulges

TL;DR

This study tests a theoretical criterion for bar formation in disk galaxies with bulges using observational data, confirming that most barred galaxies satisfy the predicted force condition.

Contribution

It validates a recent simulation-based bar formation criterion through observational analysis of a large galaxy sample.

Findings

92% of barred galaxies meet the FB < 0.13 condition

Theoretical prediction aligns well with observational data

Supports the role of bulge force in bar formation

Abstract

Earlier studies have shown that massive bulges impede bar formation in disk galaxies. Recent N-body simulations have derived a bar formation criterion that depends on the radial bulge force in a galaxy disk. We use those simulations to show that bars can form only when the force constant FB < 0.13, where FB depends on the ratio of the bulge force to the total force of the galaxy at twice the disk scale length 2R d . In this article, we test this theoretical prediction using observational data obtained from the literature. Our sample consists of 63 barred galaxies with a wide range of Hubble classes from the S 4 G catalogue for which bulge, disk and bar decomposition has been done. We find that 92 % of our sample galaxies satisfy the condition FB < 0.13 for bar formation in galaxies and hence agree with the bar formation criterion given by the simulations.