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arXiv · 2505.09782

Virgo Filaments V: Disrupting the Baryon Cycle in the NGC 5364 Galaxy Group

Abstract

The Virgo Filament Survey (VFS) is a comprehensive study of galaxies that reside in the extended filamentary structures surrounding the Virgo Cluster, out to 12 virial radii. The primary goal is to characterize all of the dominant baryonic components within galaxies and to understand whether and how they are affected by the filament environment. A key constituent of VFS is a narrowband H$\alpha$ imaging survey of over 600 galaxies, VFS-H$\alpha$. The H$\alpha$ images reveal detailed, resolved maps of the ionized gas and massive star-formation. This imaging is particularly powerful as a probe of environmentally-induced quenching because different physical processes affect the spatial distribution of star formation in different ways. In this paper, we present the first results from the VFS-H$\alpha$ for the NGC~5364 group, a low-mass ($\log_{10}(M_{dyn}/M_\odot) < 13)$ system located at the western edge of the Virgo~III filament. We combine H$\alpha$ imaging with resolved H~I observations from MeerKAT for eight group members. These galaxies exhibit peculiar morphologies, including strong distortions in the stars and the gas, truncated H~I and H$\alpha$ disks, H~I tails, extraplanar H$\alpha$ emission, and off-center H$\alpha$ emission. These signatures are suggestive of environmental processing such as tidal interactions, ram pressure stripping, and starvation. We quantify the role of ram pressure stripping expected in this group, and find that it can explain the cases of H~I tails and truncated H-alpha for all but one of the disk-dominated galaxies. Our observations indicate that multiple physical mechanisms are disrupting the baryon cycle in these group galaxies.

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BibTeXRIS

Rose A. Finn, Gregory Rudnick, Pascale Jablonka, Mpati Ramatsoku, Gautam Nagaraj, Benedetta Vulcani, Rebecca A. Koopmann, Matteo Fossati, James Agostino, Yannick Bahe, Santiago Garcia-Burillo, Gianluca Castignani, Francoise Combes, Kim Conger, Gabriella De Lucia, Vandana Desai, John Moustakas, Dara Norman, Damien Sperone-Longin, Melinda Townsend, Lizhi Xie, Daria Zakharova, Dennis Zaritsky. 2025-05-14. Virgo Filaments V: Disrupting the Baryon Cycle in the NGC 5364 Galaxy Group. https://doi.org/10.3847/1538-4357%2Fadc566

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