76 N/O-enhanced galaxies at 4<z<8.5 are observed shortly after starbursts, either in the WR enrichment phase within 10 Myr or the AGB phase after 30-40 Myr following outflows.
An updated analytic model for the attenuation by the intergalactic medium
5 Pith papers cite this work. Polarity classification is still indexing.
abstract
We present an updated version of the so-called Madau model for the attenuation by the intergalactic neutral hydrogen against the radiation from distant objects. First, we derive a distribution function of the intergalactic absorbers from the latest observational statistics of the Ly$\alpha$ forest, Lyman limit systems, and damped Ly$\alpha$ systems. The distribution function excellently reproduces the observed redshift evolutions of the Ly$\alpha$ depression and of the mean-free-path of the Lyman continuum simultaneously. Then, we derive a set of the analytic functions which describe the mean intergalactic attenuation curve for objects at $z>0.5$. The new model predicts less (or more) Ly$\alpha$ attenuation for $z\simeq3$--5 ($z>6$) sources through usual broad-band filters relative to the original Madau model. This may cause a systematic difference in the photometric redshift estimates, which is, however, still as small as about 0.05. Finally, we find a more than 0.5 mag overestimation of the Lyman continuum attenuation in the original Madau model at $z>3$, which causes a significant overcorrection against direct observations of the Lyman continuum of galaxies.
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UNVERDICTED 5representative citing papers
Bayesian continuum fitting of 66 LRDs shows the BH* model fits ~6% best, rising to ~40% under AGN-disfavoring priors, with most objects stellar/AGN-dominated and possible evolutionary trends.
JWST spectra reveal that two z~7 galaxies already show near-solar iron-to-silicon ratios with no strong odd-even effect, favoring early Type Ia supernovae over pair-instability supernovae as the source of iron enrichment.
LRDs require Compton-thick gas at moderate metallicity plus high accretion rates producing weak X-rays to explain their non-detection, implying they are not chemically pristine.
SKA-Mid is predicted to yield samples of 10-100 low-metallicity Lyman continuum emitting galaxies per square degree, enabling multi-wavelength studies of feedback processes linked to ionizing photon escape.
citing papers explorer
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Diverse Histories and Common Origins of Nitrogen-enhanced JWST Galaxies
76 N/O-enhanced galaxies at 4<z<8.5 are observed shortly after starbursts, either in the WR enrichment phase within 10 Myr or the AGB phase after 30-40 Myr following outflows.
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Between Degeneracy and Evolution: UV-to-optical Insights into the BH$^*$ Model in Little Red Dots
Bayesian continuum fitting of 66 LRDs shows the BH* model fits ~6% best, rising to ~40% under AGN-disfavoring priors, with most objects stellar/AGN-dominated and possible evolutionary trends.
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JWST Absorption-Line Analysis of UV-Bright Galaxies at $z=7.2-10.6$: Early Chemical Enrichment Traced by C, O, Mg, Al, Si, and Fe
JWST spectra reveal that two z~7 galaxies already show near-solar iron-to-silicon ratios with no strong odd-even effect, favoring early Type Ia supernovae over pair-instability supernovae as the source of iron enrichment.
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On the quenching of LRD X-ray emission by both Compton-thick gas and high accretion rates
LRDs require Compton-thick gas at moderate metallicity plus high accretion rates producing weak X-rays to explain their non-detection, implying they are not chemically pristine.
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Probing the Nature of Lyman Continuum Emitting and Low-metallicity Galaxies Using the SKA
SKA-Mid is predicted to yield samples of 10-100 low-metallicity Lyman continuum emitting galaxies per square degree, enabling multi-wavelength studies of feedback processes linked to ionizing photon escape.