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arXiv · 2510.00235

JADES: The Star Formation and Dust Attenuation Properties of Galaxies at 3<z<7

Abstract

We present the star formation and dust attenuation properties for a sample of 602 galaxies at redshifts $\rm{3<z<7}$, as part of the JADES survey. Our analysis is based on measurements of the $\rm{H}\alpha/\rm{H}\beta$ Balmer Decrement using medium resolution (R$\sim$1000) spectroscopic observations with the JWST/NIRSpec Micro-Shutter Assembly. Stellar masses and star formation rates (SFRs) are inferred with \texttt{Prospector} using deep multi-band imaging. We utilize the Balmer decrement to measure dust-corrected H$\alpha$-based SFRs, taking into account the subsolar metallicities observed in galaxies at high redshift. We confirm, with our large sample size, that the correlation between the Balmer decrement and stellar mass is already established out to $z\sim7$. We find that the relation between the Balmer decrement and stellar mass does not significantly evolve from the local universe to $z\sim7$. We investigate the UV slope as a function of the Balmer optical depth and find that the best-fit correlation for our high redshift sample is sSFR dependent and significantly different at high redshift when compared to galaxies at $z\approx 0$ and $z \approx 2$. For the highest sSFR galaxies in our sample, there is no significant correlation between the UV slope and Balmer optical depth. This is evidence that the UV slope should be used with great caution to correct for dust in high redshift galaxies.

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Charity Woodrum, Irene Shivaei, Joris Witstok, Aayush Saxena, Charlotte Simmonds, Jan Scholtz, Rachana Bhatawdekar, Andrew J. Bunker, Stéfano Carniani, Stephane Charlot, Mirko Curti, Emma Curtis-Lake, Jacopo Chevallard, Francesco D'Eugenio, Kevin Hainline, Jakob M. Helton, Roberto Maiolino, Michele Perna, Pierluigi Rinaldi, Brant Robertson, Amber Straughn, Yang Sun, Sandro Tacchella, Christina C. Williams, Chris Willott, Yongda Zhu. 2025-09-30. JADES: The Star Formation and Dust Attenuation Properties of Galaxies at 3<z<7. https://arxiv.org/abs/2510.00235

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