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arXiv · 2006.05870

Testing a theoretical prediction for bar formation in galaxies with bulges

Sandeep Kumar Kataria·Mousumi Das·Sudhanshu Barway
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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.

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Sandeep Kumar Kataria, Mousumi Das, Sudhanshu Barway. 2020-06-10. Testing a theoretical prediction for bar formation in galaxies with bulges. https://doi.org/10.1051/0004-6361%2F202037527

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