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Title: CLEAR: The Evolution of Spatially Resolved Star Formation in Galaxies between 0.5 ≲ z ≲ 1.7 Using Hα Emission Line Maps
Abstract

Using spatially resolved Hαemission line maps of star-forming galaxies, we study the spatial distribution of star formation over a wide range in redshift (0.5 ≲z≲ 1.7). Ourz∼ 0.5 measurements come from deep Hubble Space Telescope (HST) Wide Field Camera 3 G102 grism spectroscopy obtained as part of the CANDELS LyαEmission at Reionization Experiment. For star-forming galaxies with log(M*/M) ≥ 8.96, the mean Hαeffective radius is 1.2 ± 0.1 times larger than that of the stellar continuum, implying inside-out growth via star formation. This measurement agrees within 1σwith those measured atz∼ 1 andz∼ 1.7 from the 3D-HST and KMOS3Dsurveys, respectively, implying no redshift evolution. However, we observe redshift evolution in the stellar mass surface density within 1 kpc (Σ1kpc). Star-forming galaxies atz∼ 0.5 with a stellar mass of log(M*/M) = 9.5 have a ratio of Σ1kpcin Hαrelative to their stellar continuum that is lower by (19 ± 2)% compared toz∼ 1 galaxies. Σ1kpc,Hα1kpc,Contdecreases toward higher stellar masses. The majority of the redshift evolution in Σ1kpc,Hα1kpc,Contversus stellar mass stems from the fact that log(Σ1kpc,Hα) declines twice as much as log(Σ1kpc,Cont) fromz∼ 1 to 0.5 (at a fixed stellar mass of log(M*/M) = 9.5). By comparing our results to the TNG50 cosmological magneto-hydrodynamical simulation, we rule out dust as the driver of this evolution. Our results are consistent with inside-out quenching following in the wake of inside-out growth, the former of which drives the significant drop in Σ1kpc,Hαfromz∼ 1 toz∼ 0.5.

 
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NSF-PAR ID:
10371673
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
937
Issue:
1
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 16
Size(s):
["Article No. 16"]
Sponsoring Org:
National Science Foundation
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