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arXiv · 1802.07277

Exploring the limits of AGN feedback: black holes and the star formation histories of low-mass galaxies

Ignacio Martin-Navarro·Mar Mezcua
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Abstract

Energy feedback, either from active galactic nuclei (AGN) or from supernovae, is required to understand galaxy formation within a $\Lambda$-Cold Dark Matter cosmology. We study a sample of 127 low-mass galaxies, comparing their stellar populations properties to the mass of the central supermassive black hole, in order to investigate the effect of AGN feedback. We find a loose coupling between star formation history and black hole mass, which seems to suggest that AGN activity does not dominate baryonic cooling in low-mass galaxies. We also find that a break in the $M_\bullet$-$\sigma$ relation marks a transitional stellar mass, M$_\mathrm{trans}=3.4\pm2.1 \times 10^{10}$ M$_{\odot}$, remarkably similar to M$_\star$. Our results are in agreement with a bi-modal star formation process where the AGN-dominated feedback of high-mass galaxies transitions towards a supernovae-driven regime in low-mass systems, as suggested by numerical simulations.

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Ignacio Martin-Navarro, Mar Mezcua. 2018-02-20. Exploring the limits of AGN feedback: black holes and the star formation histories of low-mass galaxies. https://doi.org/10.3847/2041-8213/aab103

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