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arXiv · 2606.26813

Feeding and Feedback in Dwarf Galaxies (FeeD) -- I. Evidence of nuclear ultra-fast and galaxy-scale outflows in the dwarf galaxy Arp 151

Santanu Mondal·Ankit Patel·Mar Mezcua·Ravi Joshi·Yerong Xu·K. Aditya·Smitha Subramanian·Victor Rodriguez Morales
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Abstract

Feeding and feedback regulated by supermassive black holes (SMBHs) play a central role in galaxy growth and evolution, yet these processes remain poorly understood in low-mass galaxies. In particular, the presence, properties, and role of ultra-fast nuclear outflows (UFOs) in low-mass galaxy systems are largely unexplored. We analyze available NuSTAR X-ray observations of Arp 151 and find a possible evidence ($\sim 2σ$ confidence) for a fast outflow with a velocity of $\sim0.18c$ from the central BH. Furthermore, we have also detected an optical galaxy-scale outflow in MaNGA Integral Field Unit data. The estimated nuclear and galaxy-scale mass outflow rates are $\sim0.015$ $M_\odot$/yr from {\it NuSTAR} and $\sim0.43$ $M_\odot$/yr from MaNGA, respectively. Our estimates suggest that such outflows may significantly regulate the feedback process in the galaxy. Comparing the kinetics of the UFO and the galaxy-scale outflow indicates that they are in the momentum-conserving phase. This tentative detection implies that dwarf galaxies are also able to generate UFOs, which so far have been detected in massive galaxies. Thus, the AGN feedback may also be important for the evolution of the dwarf galaxies.

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Santanu Mondal, Ankit Patel, Mar Mezcua, Ravi Joshi, Yerong Xu, K. Aditya, Smitha Subramanian, Victor Rodriguez Morales. 2026-06-25. Feeding and Feedback in Dwarf Galaxies (FeeD) -- I. Evidence of nuclear ultra-fast and galaxy-scale outflows in the dwarf galaxy Arp 151. https://arxiv.org/abs/2606.26813

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