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arXiv · 2211.08937

Dusty winds clear JWST super-early galaxies

Fabrizio Fiore·Andrea Ferrara·Manuela Bischetti·Chiara Feruglio·Andrea Travascio
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Abstract

The JWST discovery of a number of super-early (redshift $z>10$), blue galaxies requires these systems to be essentially dust-free in spite of their large stellar masses. A possible explanation is that dust is evacuated by radiatively-driven outflows. We test this hypothesis by deriving the Eddington ratio $\lambda_E=L_{\rm bol}/L_{E}$, where $L_{\rm bol}$ is the bolometric luminosity produced by star-formation and possible black hole accretion, for 134 galaxies at $6.5< z <16$. We find a strong anti-correlation between $\lambda_E$ and dust UV optical depth, $\tau_{1500} \propto \lambda_E^{-0.63}$; also, $\lambda_E$ increases with redshift. We confirm that galaxies exceeding a specific star formation rate ${\rm sSFR} > 13\, \rm Gyr^{-1}$ develop powerful outflows clearing the galaxy from its dust. This result is supported by ALMA dust continuum non-detections in three super-early systems.

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Fabrizio Fiore, Andrea Ferrara, Manuela Bischetti, Chiara Feruglio, Andrea Travascio. 2022-11-16. Dusty winds clear JWST super-early galaxies. https://doi.org/10.3847/2041-8213%2Facb5f2

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