Spatially resolved JWST observations of lensed LAE HCM 6A at z=6.57 reveal Lyα escaping from a dust-cleared central clump in the youngest region, with age-dependent Calzetti-like attenuation curves.
Hitting the slopes: A spectroscopic view of UV continuum slopes of galaxies reveals a reddening at z > 9.5
5 Pith papers cite this work. Polarity classification is still indexing.
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Pith papers citing it
abstract
The UV continuum slope of galaxies, $\beta$, is a powerful diagnostic. Understanding the redshift evolution of $\beta$ and its dependence on key galaxy properties can shed light on the evolution of galaxy physical properties over cosmic time. In this study, we present $\beta$ measurements for 295 spectroscopically confirmed galaxies at $5.5<z<14.3$ selected primarily from JADES, where $\beta$ has been measured from high quality JWST NIRSpec/PRISM spectra. We find a median $\beta=-2.3$ across our full sample, and find mild increase in blueness of $\beta$ with increasing redshift and fainter UV magnitudes. Interestingly, we find evidence for the average $\beta$ at $z > 9.5$ to begin to redden, deviating from the trend observed at $z < 9.5$. By producing stacked spectra in bins of redshift and $\beta$, we derive trends between $\beta$ and dust attenuation, metallicity, ionization parameter, and stellar age indicators directly from spectra, finding a lack of dust attenuation to be the dominant driver of bluer $\beta$ values. We further report six galaxies with $\beta<-3.0$, which show a range of spectroscopic properties and signs of significant LyC photon leakage. Finally, we show that the redder $\beta$ values at $z > 9.5$ may require rapid build-up of dust reservoirs in the very early Universe or a significant contribution from the nebular continuum emission to the observed UV spectra, with the nebular continuum fraction depending on the gas temperatures and densities. Our modeling shows that in the absence of dust, nebular emission at $T > 15,000$ K can reproduce the range of $\beta$ that we see in our sample. Higher gas temperatures driven by hot, massive stars can boost the fraction of nebular continuum emission, potentially explaining the observed $\beta$ values as well as bright UV magnitudes seen across galaxies at $z > 10$.
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astro-ph.GA 5representative citing papers
Lyα radiation pressure mildly reduces gas-to-star conversion efficiency in dense high-redshift clusters while dominating the launch of rapid outflows.
A massive galaxy at z=9.3 shows bursty star formation with a recent downturn and sits in a small ionized bubble in a neutral IGM.
Application of the Attenuation-Free Model to JWST super-early galaxies yields massive halos with moderate efficiencies and supports an evolutionary sequence from dust-reddened to UV-clear phases driven by outflows.
JADES DR5 delivers 2081 z_phot > 8 galaxy candidates with UV slope trends, morphological evidence of clumpy growth, and improved photo-z methods tested on a spectroscopic subsample.
citing papers explorer
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Resolving dust and Ly{\alpha} emission in a lensed galaxy at the epoch of reionization with JWST/CANUCS
Spatially resolved JWST observations of lensed LAE HCM 6A at z=6.57 reveal Lyα escaping from a dust-cleared central clump in the youngest region, with age-dependent Calzetti-like attenuation curves.
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Lyman-alpha Radiation Pressure in Dense Star Clusters: Implications for Star Formation and Winds at Cosmic Dawn
Lyα radiation pressure mildly reduces gas-to-star conversion efficiency in dense high-redshift clusters while dominating the launch of rapid outflows.
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SPURS: Bursty Star Formation in an Extremely Luminous Weak Emission Line Galaxy at $z=9.3$
A massive galaxy at z=9.3 shows bursty star formation with a recent downturn and sits in a small ionized bubble in a neutral IGM.
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No Blue without Red: Evolutionary Properties of Super-Early Galaxies
Application of the Attenuation-Free Model to JWST super-early galaxies yields massive halos with moderate efficiencies and supports an evolutionary sequence from dust-reddened to UV-clear phases driven by outflows.
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JWST Advanced Deep Extragalactic Survey (JADES) Data Release 5: Photometrically Selected Galaxy Candidates at z > 8
JADES DR5 delivers 2081 z_phot > 8 galaxy candidates with UV slope trends, morphological evidence of clumpy growth, and improved photo-z methods tested on a spectroscopic subsample.