| Autor: |
J. R. Rigby, E. Wuyts, T. L. Johnson, K. Sharon, K. Whitaker, M. Florian, M. D. Gladders, J. Lotz, M. Bayliss |
| Předmět: |
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| Zdroj: |
Astrophysical Journal; 7/10/2017, Vol. 843 Issue 2, p1-1, 1p |
| Abstrakt: |
For lensed galaxy SGAS J111020.0+645950.8 at redshift z = 2.481, which is magnified by a factor of 28 ± 8, we analyze the morphology of star formation, as traced by rest-frame ultraviolet emission, in both the highly magnified source plane and simulations of how this galaxy would appear without lensing magnification. Were this galaxy not lensed, but rather drawn from a Hubble Space Telescope deep field, we would conclude that almost all its star formation arises from an exponential disk (Sérsic index of 1.0 ± 0.4) with an effective radius of measured from two-dimensional fitting to F606W using Galfit, and measured by fitting a radial profile to F606W elliptical isophotes. At the normal spatial resolution of the deep fields, there is no sign of clumpy star formation within SGAS J111020.0+645950.8. However, the enhanced spatial resolution enabled by gravitational lensing tells a very different story; much of the star formation arises in two dozen clumps with sizes of r = 30–50 pc spread across the 7 kpc length of the galaxy. The color and spatial distribution of the diffuse component suggests that still-smaller clumps are unresolved. Despite this clumpy, messy morphology, the radial profile is still well-characterized by an exponential profile. In this lensed galaxy, stars are forming in complexes with sizes well below 100 pc; such sizes are wholly unexplored by surveys of galaxy evolution at . [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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