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arXiv · 2503.05171

Formation of the dark-matter deficient S0 galaxy NGC 4111 under the tidal interactions

Mei Ai·Ming Zhu·Nai-ping Yu·Jin-long Xu·Xiao-lan Liu·Yingjie Jing·Qian Jiao·Yao Liu·Chuan-peng Zhang·Jie Wang·Peng Jiang
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Abstract

We present the high-sensitivity and large-scale atomic hydrogen (HI) observations towards lenticular (S0) galaxy NGC 4111 using the Five-hundred-meter Aperture Spherical Radio Telescope (FAST). The column density map shows that NGC4111 and seven other different types of galaxies share a huge HI gas complex. The data also suggest that NGC 4111 is interacting with seven galaxies. Moreover, we identified a rotating gas disk associated with NGC 4111 from the HI complex. Still, the HI disk rotation direction has deviated from its stellar disk about 34.2$^{\circ}$, indicating that the NGC 4111 galaxy is undergoing a transition from a spiral galaxy to an S0 galaxy by the tidal interactions. The obtained dark matter-to-stellar mass ratio of NGC4111 is 3.1$\pm$0.7, which is lower than the average value of the Local Universe, implying that the interactions may strip its dark matter. Our results suggest that in a galaxy group environment, tidal interactions have a significant effect on galaxy features.

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Mei Ai, Ming Zhu, Nai-ping Yu, Jin-long Xu, Xiao-lan Liu, Yingjie Jing, Qian Jiao, Yao Liu, Chuan-peng Zhang, Jie Wang, Peng Jiang. 2025-03-07. Formation of the dark-matter deficient S0 galaxy NGC 4111 under the tidal interactions. https://arxiv.org/abs/2503.05171

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