Journal
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Volume 514, Issue 2, Pages 1921-1939Publisher
OXFORD UNIV PRESS
DOI: 10.1093/mnras/stac1368
Keywords
galaxies: evolution; galaxies: high-redshift; galaxies: photometry
Categories
Funding
- BEIS capital funding via STFC capital grants [ST/K00042X/1, ST/P002293/1, ST/R002371/1, ST/S002502/1]
- Durham University
- Royal Society [RGF/EA/181016]
- European Research Council [818930]
- Danish National Research Foundation [140]
- National Research Council Canada Plaskett Fellowship
- Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) [CE170100013]
- STFC operations grant [ST/R000832/1]
- European Research Council (ERC) [818930] Funding Source: European Research Council (ERC)
Ask authors/readers for more resources
This study presents the sizes of galaxies at z >= 5 in simulations, including their intrinsic and observed sizes. The inclusion of dust leads to larger observed sizes compared to intrinsic sizes, with the increase driven by dust concentration in the core of galaxies. At fixed luminosity, there is a galaxy size redshift evolution, and the wavelength dependence of the size-luminosity relation is expected to be probed by the James Webb Space Telescope.
We present the intrinsic and observed sizes of galaxies at z >= 5 in the First Light And Reionisation Epoch Simulations (flares). We employ the large effective volume of flares to produce a sizeable sample of high-redshift galaxies with intrinsic and observed luminosities and half-light radii in a range of rest-frame ultraviolet (UV) and visual photometric bands. This sample contains a significant number of intrinsically ultracompact galaxies in the far-UV (1500 angstrom), leading to a negative intrinsic far-UV size-luminosity relation. However, after the inclusion of the effects of dust these same compact galaxies exhibit observed sizes that are as much as 50 times larger than those measured from the intrinsic emission, and broadly agree with a range of observational samples. This increase in size is driven by the concentration of dust in the core of galaxies, heavily attenuating the intrinsically brightest regions. At fixed luminosity we find a galaxy size redshift evolution with a slope of m = 1.21-1.87 depending on the luminosity sample in question, and we demonstrate the wavelength dependence of the size-luminosity relation that will soon be probed by the James Webb Space Telescope.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available