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arXiv · 2511.14257

Positive AGN feedback in the outskirts of nearby barred spiral galaxies?

Bannanje Ananthamoorthy·Debbijoy Bhattacharya·P. Sreekumar
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Abstract

Observational evidence regarding the impact of AGN feedback on star formation (SF) in non-jetted galaxies is limited. With the available high-resolution UV observations from AstroSat-UVIT, complemented by GALEX, we studied the SF properties in the outskirts ($>0.5R_{25}$) of six AGN-host galaxies and compared them with four non-AGN galaxies of similar morphology. We observed a higher SF rate density ($\Sigma_{\text{SFR}}$) for the UV knots in AGN-host galaxies, and it falls off less rapidly compared to non-AGN galaxies, suggesting positive AGN feedback in the outskirts of AGN-host galaxies. Additionally, FUV attenuation (A$_{\text{FUV}}$) is also enhanced in the outer regions and falls less rapidly in AGN-host compared to non-AGN, indicating that the feedback could be coupled with dust. We speculate that the radiation-pressure-driven and/or wind mode AGN feedback could be at play even in low-luminosity nearby AGN-host galaxies.

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Bannanje Ananthamoorthy, Debbijoy Bhattacharya, P. Sreekumar. 2025-11-18. Positive AGN feedback in the outskirts of nearby barred spiral galaxies?. https://doi.org/10.1017/pasa.2025.10118

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