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arXiv · 2309.11982

Properties of Barred Galaxies with the Environment: I. the case of the Virgo cluster

J. Alfonso L. Aguerri·Virginia Cuomo·Azahara Rojas-Roncero·Lorenzo Morelli
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Abstract

Barred structures are widespread in a considerable fraction of galactic discs, spanning diverse environments and galaxy luminosities. The environment likely exerts a significant influence on bar formation. It is plausible that the structural parameters of bars resulting from tidal interactions in high-density galactic environments differ from those formed through internal disc instabilities in isolated galaxies. To empirically test this scenario, a viable approach is to compare the structural parameters of bars in galaxies situated within distinct environments. We have collected data on the bar radius and bar strength for a sample of 36 SB0 and SBa galaxies located within the Virgo cluster. Additionally, we analyzed a sample of 46 field galaxies with similar morphologies and luminosity range. The analysis reveals that the bar radius exhibits a correlation with galaxy luminosity, indicating that larger bars are typically found in more luminous galaxies. When comparing galaxies with fixed luminosities, the field galaxies display larger bar radii compared to those in the Virgo cluster. However, when the bar radius is scaled by the size of the galaxy, the disparity diminishes and the scaled bars in the Virgo cluster and the field exhibit similar sizes. This is because galaxies of similar luminosities tend to be larger in the field environment compared to the cluster and because the bars adapt to the discs in which they live. Regarding the bar strength, no significant differences were observed for bright galaxies ($M_{r} < -19.5$) between those located in the Virgo cluster and those in the field. In contrast, faint galaxies ($M_{r} > -19.5$) show stronger bars in the field than in the cluster.

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J. Alfonso L. Aguerri, Virginia Cuomo, Azahara Rojas-Roncero, Lorenzo Morelli. 2023-09-21. Properties of Barred Galaxies with the Environment: I. the case of the Virgo cluster. https://arxiv.org/abs/2309.11982

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