JWST spectra of six z=5-9 galaxies show low-ionization covering fractions of 0.2-0.9 and diverse kinematics including blueshifted outflows, indicating heterogeneous multiphase ISM.
Rest-Frame Ultraviolet Spectra of z~3 Lyman Break Galaxies
6 Pith papers cite this work. Polarity classification is still indexing.
abstract
We present the results of a systematic study of the rest-frame UV spectroscopic properties of Lyman Break Galaxies (LBGs). The database of almost 1000 LBG spectra proves useful for constructing high S/N composite spectra. The composite spectrum of the entire sample reveals a wealth of features attributable to hot stars, HII regions, dust, and outflowing neutral and ionized gas. By grouping the database according to galaxy parameters such as Lyman-alpha equivalent width, UV spectral slope, and interstellar kinematics, we isolate some of the major trends in LBG spectra which are least compromised by selection effects. We find that LBGs with stronger Lyman-alpha emission have bluer UV continua, weaker low-ionization interstellar absorption lines, smaller kinematic offsets between Lyman-alpha and the interstellar absorption lines, and lower star-formation rates. There is a decoupling between the dependence of low- and high-ionization outflow features on other spectral properties. Most of the above trends can be explained in terms of the properties of the large-scale outflows seen in LBGs. According to this scenario, the appearance of LBG spectra is determined by a combination of the covering fraction of outflowing neutral gas which contains dust, and the range of velocities over which this gas is absorbing. Higher sensitivity and spectral resolution observations are still required for a full understanding of the covering fraction and velocity dispersion of the outflowing neutral gas in LBGs, and its relationship to the escape fraction of Lyman continuum radiation in galaxies at z~3.
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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.
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.
Far-IR stacking of ~4000 LAEs at z=2-6 yields detections in massive AGN hosts with low f_esc(Lyα) (1-7%) and higher values (>10%) in undetected stacks, plus elevated IRX relative to typical star-forming galaxies.
MUST is a planned 6.5m Stage-V spectroscopic survey telescope targeting 100M+ galaxies and quasars to z~5.5 for large-scale structure cosmology studies.
The paper reviews dust production, destruction and growth processes in galaxies, compiles literature data on comoving dust mass density, presents evidence for and against interstellar dust growth, and identifies the high-redshift dust budget as needing further study.
citing papers explorer
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JWST absorption line spectroscopy with SPURS: ISM covering fractions and kinematics in individual galaxies at $z=5-9$
JWST spectra of six z=5-9 galaxies show low-ionization covering fractions of 0.2-0.9 and diverse kinematics including blueshifted outflows, indicating heterogeneous multiphase ISM.
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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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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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Far-infrared observations of dust in Ly$\alpha$ emitters at z=2-6
Far-IR stacking of ~4000 LAEs at z=2-6 yields detections in massive AGN hosts with low f_esc(Lyα) (1-7%) and higher values (>10%) in undetected stacks, plus elevated IRX relative to typical star-forming galaxies.
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MUltiplexed Survey Telescope (MUST) Science White Paper I: Overview of Large-Scale Structure Cosmology in the Era of Stage-V Spectroscopic Surveys
MUST is a planned 6.5m Stage-V spectroscopic survey telescope targeting 100M+ galaxies and quasars to z~5.5 for large-scale structure cosmology studies.
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Interstellar dust production, destruction and effects of dust depletion in galaxies
The paper reviews dust production, destruction and growth processes in galaxies, compiles literature data on comoving dust mass density, presents evidence for and against interstellar dust growth, and identifies the high-redshift dust budget as needing further study.