2025MNRAS.541.3606T -
Mon. Not. R. Astron. Soc., 541, 3606-3626 (2025/August-3)
Bridging theory and observations: insights into star formation efficiency and dust attenuation in z > 5 Galaxies.
TOYOUCHI D., YAJIMA H., FERRARA A. and NAGAMINE K.
Abstract (from CDS):
We investigate early galaxy evolution by modeling self-consistently their radially resolved evolution of gas, stars, heavy elements, and dust content. Our model successfully reproduces various observed properties of JWST-identified galaxies at $z > 5$, including sizes, stellar masses, star formation rates (SFR), metallicities, and dust-to-stellar mass ratios. We show that the star formation efficiency (SFE), $f_\ast \equiv {\rm SFR}/(f_{\rm b} \dot{M}_{\rm h})$, is regulated by the global equilibrium between cosmological gas inflows, star formation, and gas outflows. Our model predicts $f_\ast \lesssim 20~{{\ \rm per\ cent}}$ for galaxies with halo masses of $M_{\rm h} \sim 10^{11\!-\!12}\, {\rm M_\odot }$ down to $z = 5$, allowing them to reach intrinsic ultraviolet (UV) magnitudes of $M_{\rm UV} \lesssim -22~{\rm mag}$; when dust attenuation is ignored, the predicted UV luminosity function (LF) at $z \sim 12$ agrees well with observations. However, our model also suggests that these galaxies would be heavily obscured by dust, with high optical depths at 1500 Å of $\tau _{1500} \gtrsim 10$, causing the dust-attenuated UV LF to fall significantly below the observed one. This discrepancy highlights the need for mechanisms that mitigate strong dust attenuation, such as dust evacuation from star-forming regions and/or preferential production of large dust grains. Further exploration of these processes is essential for understanding the early stages of galaxy evolution.
Abstract Copyright:
© 2025 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society.
Journal keyword(s):
galaxies: evolution - galaxies: high-redshift - galaxies: luminosity function, mass function - galaxies: star formation
Status at CDS
:
Acronym for new objects described in the dictionary of nomenclature and being created in SIMBAD.
Simbad objects:
16
Full paper
View the references in ADS
To bookmark this query, right click on this link: simbad:2025MNRAS.541.3606T and select 'bookmark this link' or equivalent in the popup menu