Anisotropic quenching is detected at the highest redshift yet and linked to preprocessing dominating over intrahalo effects by ~20% along the major axis in a delay-then-rapid quenching model informed by cluster accretion histories.
Hitting the slopes: A spectroscopic view of UV continuum slopes of galaxies reveals a reddening at z > 9.5
9 Pith papers cite this work. Polarity classification is still indexing.
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 $z > 10$.
representative citing papers
Filter-substrate refraction causes dominant lateral shifts yielding 0.3-0.4% PSF size and ellipticity residuals across most Roman bands that exceed weak lensing requirements by an order of magnitude, while longitudinal defocus shifts remain negligible.
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.
Analysis of ~100 JWST LRDs finds redder, compact UV emission with Fe II/Mg II ~8-10 and correlations suggesting central red continuum (β_UV~0) beyond host galaxy contribution.
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.
Analysis of JWST/NIRSpec Prism spectra for 25 z>=10 galaxies finds burstiness correlates with strong UV lines, short depletion times, and DLA-induced redshift biases of 0.39 and 0.14 with marginal impact on UV luminosity density.
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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Anisotropic quenching beyond $z=1$ and its implications for preprocessing around high-redshift galaxy clusters
Anisotropic quenching is detected at the highest redshift yet and linked to preprocessing dominating over intrahalo effects by ~20% along the major axis in a delay-then-rapid quenching model informed by cluster accretion histories.
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Modeling the impact of filter-substrate refraction in the Roman point spread function
Filter-substrate refraction causes dominant lateral shifts yielding 0.3-0.4% PSF size and ellipticity residuals across most Roman bands that exceed weak lensing requirements by an order of magnitude, while longitudinal defocus shifts remain negligible.
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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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The UV Side of Little Red Dots: Red, Compact, and Iron-Enhanced Rest-UV Emission with a Strong Downturn around Ly$\alpha$
Analysis of ~100 JWST LRDs finds redder, compact UV emission with Fe II/Mg II ~8-10 and correlations suggesting central red continuum (β_UV~0) beyond host galaxy contribution.
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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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JWST spectroscopy of galaxies at $z>10$: Damped Ly$\alpha$ absorbers reveal efficient star formation and hidden redshift biases
Analysis of JWST/NIRSpec Prism spectra for 25 z>=10 galaxies finds burstiness correlates with strong UV lines, short depletion times, and DLA-induced redshift biases of 0.39 and 0.14 with marginal impact on UV luminosity density.
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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.