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Dust has been detected in high-redshift ($z>5$) galaxies but its origin is still being debated. Dust production in high-redshift galaxies could be dominated by stellar production or by accretion (dust growth) in the interstellar medium. Previous studies have shown that these two dust sources predict different grain size distributions, which lead to significantly different extinction curves. In this paper, we investigate how the difference in the extinction curves affects the dust attenuation properties of galaxies by performing radiative transfer calculations. To examine the major effects of the dust--stars distribution geometry, we adopt two representative cases in spherical symmetry: the well-mixed geometry (stars and dust are homogeneously mixed) and the two-layer geometry (young stars are more concentrated in the centre). In both cases, we confirm that the attenuation curve can be drastically steepened by scattering and by different optical depths between young and old stellar populations, and can be flattened by the existence of unobscured stellar populations. We can reproduce similar attenuation curves even with very different extinction curves. Thus, we conclude that it is difficult to distinguish the dust sources only with attenuation curves. However, if we include information on dust emission and plot the IRX (infrared excess)--$beta$ (ultraviolet spectral slope) relation, different dust sources predict different positions in the IRX--$beta$ diagram. A larger $beta$ is preferred under a similar IRX if dust growth is the dominant dust source.
A diverse range of dust attenuation laws is found in star-forming galaxies. In particular, Tress et al. (2018) studied the SHARDS survey to constrain the NUV bump strength (B) and the total-to selective ratio (Rv) of 1,753 star-forming galaxies in th
We present predictions for high redshift ($z=2-10$) galaxy populations based on the IllustrisTNG simulation suite and a full Monte Carlo dust radiative transfer post-processing. Specifically, we discuss the ${rm H}_{alpha}$ and ${rm H}_{beta}$ + $[rm
SPICA is one of the key projects for the future. Not only its instrument suite will open up a discovery window but they will also allow to physically understand some of the phenomena that we still do not understand in the high-redshift universe. Usin
The discoveries of huge amounts of dust and unusual extinction curves in high-redshift quasars (z > 4) cast challenging issues on the origin and properties of dust in the early universe. In this Letter, we investigate the evolutions of dust content a
We use a sample of 532 star-forming galaxies at redshifts $zsim 1.4-2.6$ with deep rest-frame optical spectra from the MOSFIRE Deep Evolution Field (MOSDEF) survey to place the first constraints on the nebular attenuation curve at high redshift. Base