REVIEW 7 cited by
EPOCHS III: Unbiased UV continuum slopes at 6.5<z<13 from combined PEARLS GTO and public JWST NIRCam imaging
Not yet reviewed by Pith; the record is open.
This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.
SPECIMEN: schema-true, not a live event
T0 review · schema-true
One-sentence machine reading of the paper's core claim.
pith:XXXXXXXX · record.json · timestamp
abstract
We present an analysis of rest-frame UV continuum slopes, $\beta$, using a sample of 1011 galaxies at $6.5<z<13$ from the EPOCHS photometric sample collated from the GTO PEARLS and public ERS/GTO/GO (JADES, CEERS, NGDEEP, GLASS) JWST NIRCam imaging across $178.9~\mathrm{arcmin}^2$ of unmasked blank sky. We correct our UV slopes for the photometric error coupling bias using $200,000$ power law SEDs for each $\beta=\{-1,-1.5,-2,-2.5,-3\}$ in each field, finding biases as large as $\Delta\beta\simeq-0.55$ for the lowest SNR galaxies in our sample. Additionally, we simulate the impact of rest-UV line emission (including Ly$\alpha$) and damped Ly$\alpha$ systems on our measured $\beta$, finding biases as large as $0.5-0.6$ for the most extreme systems. We find a decreasing trend with redshift of $\beta=-1.51\pm0.08-(0.097\pm0.010)\times z$, with potential evidence for Pop.~III stars or top-heavy initial mass functions (IMFs) in a subsample of 68 $\beta+\sigma_{\beta}<-2.8$ galaxies. At $z\simeq11.5$, we measure an extremely blue $\beta(M_{\mathrm{UV}}=-19)=-2.73\pm0.06$, deviating from simulations, indicative of low-metallicity galaxies with non-zero Lyman continuum escape fractions $f_{\mathrm{esc, LyC}}\gtrsim0$ and minimal dust content. The observed steepening of $\mathrm{d}\beta/\mathrm{d}\log_{10}(M_{\star}/\mathrm{M}_{\odot})$ from $0.22\pm0.02$ at $z=7$ to $0.81\pm0.13$ at $z=11.5$ implies that dust produced in core-collapse supernovae (SNe) at early times may be ejected via outflows from low mass galaxies. We also observe a flatter $\mathrm{d}\beta/\mathrm{d}M_{\mathrm{UV}}=0.03\pm0.02$ at $z=7$ and a shallower $\mathrm{d}\beta/\mathrm{d}\log_{10}(M_{\star} / \mathrm{M}_{\odot})$ at $z<11$ than seen by HST, unveiling a new population of low mass, faint, galaxies reddened by dust produced in the stellar winds of asymptotic giant branch (AGB) stars or carbon-rich Wolf-Rayet binaries.
Forward citations
Cited by 7 Pith papers
-
Not all protoclusters host evolved galaxies: Evidence for reduced environmental effects in a lower halo mass protocluster at $z = 7.66$
A z=7.66 protocluster with an extreme overdensity hosts galaxies that are still young and star-forming, implying environmental quenching only begins in haloes above roughly 10^11.5 solar masses.
-
Deep JWST spectroscopy of galaxies in a candidate ionized bubble at $z = 8.7$: probing reionization at pMpc scales with Ly$\alpha$ emission
Lyα transmission in the z=8.7 EGS volume is T_IGM=0.26+0.25−0.14, consistent with the field average and mildly inconsistent with a 2-pMpc ionized bubble, making such a bubble unlikely.
-
The impact of medium-width bands on the selection, and subsequent luminosity function measurements, of high-z galaxies
Using the JADES Origins Field, the authors show that medium-band photometry modestly improves high-z galaxy selection completeness, while bluer broadband depth matters most for reducing contamination.
-
Morphological Demographics of Galaxies at $z\sim 10-16$: Log-Normal Size Distribution and Exponential Profiles Consistent with the Disk Formation Scenario
Galaxies at z=10-16 have a log-normal size distribution with sigma 0.52, nearly uniform axis ratios, and exponential profiles, consistent with early disk formation.
-
Synergising semi-analytical models and hydrodynamical simulations to interpret JWST data from the first billion years
A semi-analytic model seeded with simulation-derived star formation rules reproduces JWST's bright galaxies at z>11 via a top-heavy IMF or boosted star formation, and finds low-mass galaxies drove reionisation.
-
Physical properties of galaxies and the UV Luminosity Function from $z\sim6$ to $z\sim14$ in COSMOS-Web
A 3,099-galaxy JWST sample at z~6-14 shows a bright-end UV luminosity function excess at z~9-12 relative to evolving Schechter-function predictions, with non-evolving blue UV slopes.
-
Dissecting the massive pristine, neutral gas reservoir of a remarkably bright galaxy at z = 14.179
JADES-GS-z14-0 at z=14.179 contains a neutral hydrogen reservoir of about 10^9.8 solar masses, implying a gas fraction above 90 percent.
Discussion (0). Continue with ORCID to comment.