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Geometry effects on dust attenuation curves with different grain sources at high redshift
- Source :
- MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
- Publication Year :
- 2021
- Publisher :
- Oxford University Press (OUP), 2021.
-
Abstract
- 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.<br />Comment: 11 pages, 4 figures, accepted for publication in MNRAS
- Subjects :
- DISC GALAXIES
Extinction (astronomy)
FOS: Physical sciences
Geometry
SPECTRAL ENERGY-DISTRIBUTIONS
Astrophysics::Cosmology and Extragalactic Astrophysics
complex mixtures
RADIATIVE-TRANSFER CODE
Radiative transfer
Astrophysics::Solar and Stellar Astrophysics
STELLAR RADIATION
evolution [galaxies]
Astrophysics::Galaxy Astrophysics
EXTINCTION CURVES
Physics
Infrared excess
ISM [galaxies]
extinction
numerical [methods]
STAR-FORMING CLOUDS
Astronomy and Astrophysics
Astrophysics - Astrophysics of Galaxies
EVOLUTION
Redshift
Accretion (astrophysics)
Galaxy
respiratory tract diseases
Interstellar medium
Stars
Physics and Astronomy
radiative transfer
Space and Planetary Science
Astrophysics of Galaxies (astro-ph.GA)
MULTIPLE-SCATTERING
CLUMPY MEDIA
dust
Astrophysics::Earth and Planetary Astrophysics
high-redshift [galaxies]
INTERSTELLAR DUST
Subjects
Details
- ISSN :
- 13652966 and 00358711
- Volume :
- 507
- Database :
- OpenAIRE
- Journal :
- Monthly Notices of the Royal Astronomical Society
- Accession number :
- edsair.doi.dedup.....d3a05505933ce19d918b5879dbeabd6a