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arXiv · 2411.02352

Virgo Filaments IV: Using WISE to Measure the Modification of Star-Forming Disks in the Extended Regions Around the Virgo Cluster

Abstract

Recent theoretical work and targeted observational studies suggest that filaments are sites of galaxy preprocessing. The aim of the WISESize project is to directly probe galaxies over the full range of environments to quantify and characterize extrinsic galaxy quenching in the local Universe. In this paper, we use GALFIT to measure the infrared 12$μ$m ($R_{12}$) and 3.4$μ$m ($R_{3.4}$) effective radii of 603 late-type galaxies in and surrounding the Virgo cluster. We find that Virgo cluster galaxies show smaller star-forming disks relative to their field counterparts at the $2.5σ$ level, while filament galaxies show smaller star-forming disks to almost $1.5σ$. Our data, therefore, show that cluster galaxies experience significant effects on their star-forming disks prior to their final quenching period. There is also tentative support for the hypothesis that galaxies are preprocessed in filamentary regions surrounding clusters. On the other hand, galaxies belonging to rich groups and poor groups do not differ significantly from those in the field. We additionally find hints of a positive correlation between stellar mass and size ratio for both rich group and filament galaxies, though the uncertainties on these data are consistent with no correlation. We compare our size measurements with the predictions from two variants of a state-of-the-art semi-analytic model (SAM), one which includes starvation and the other incorporating both starvation and ram-pressure stripping (RPS). Our data appear to disfavor the SAM, which includes RPS for the rich group, filament, and cluster samples, which contributes to improved constraints for general models of galaxy quenching.

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BibTeXRIS

Kim Conger, Gregory Rudnick, Rose A. Finn, Gianluca Castignani, John Moustakas, Benedetta Vulcani, Daria Zakharova, Lizhi Xie, Francoise Combes, Pascale Jablonka, Yannick Bahé, Gabriella De Lucia, Vandana Desai, Rebecca A. Koopmann, Dara Norman, Melinda Townsend, Dennis Zaritsky. 2025-01-17. Virgo Filaments IV: Using WISE to Measure the Modification of Star-Forming Disks in the Extended Regions Around the Virgo Cluster. https://arxiv.org/abs/2411.02352

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