TY - JOUR
T1 - Early Results from GLASS-JWST. V
T2 - The First Rest-frame Optical Size-Luminosity Relation of Galaxies at z > 7
AU - Yang, L.
AU - Morishita, T.
AU - Leethochawalit, N.
AU - Castellano, M.
AU - Calabrò, A.
AU - Treu, T.
AU - Bonchi, A.
AU - Fontana, A.
AU - Mason, C.
AU - Merlin, E.
AU - Paris, D.
AU - Trenti, M.
AU - Roberts-Borsani, G.
AU - Bradac, M.
AU - Vanzella, E.
AU - Vulcani, B.
AU - Marchesini, D.
AU - Ding, X.
AU - Nanayakkara, T.
AU - Birrer, S.
AU - Glazebrook, K.
AU - Jones, T.
AU - Boyett, K.
AU - Santini, P.
AU - Strait, V.
AU - Wang, X.
N1 - Publisher Copyright:
© 2022. The Author(s). Published by the American Astronomical Society.
PY - 2022/10/1
Y1 - 2022/10/1
N2 - We present the first rest-frame optical size-luminosity relation of galaxies at z > 7, using the NIRCam imaging data obtained by the GLASS James Webb Space Telescope Early Release Science (GLASS-JWST-ERS) program, providing the deepest extragalactic data of the ERS campaign. Our sample consists of 19 photometrically selected bright galaxies with m F444W ≤ 27.8 at 7 < z < 9 and m F444W < 28.2 at z ∼ 9−15. We measure the size of the galaxies in five bands, from rest-frame optical (∼4800 Å) to the UV (∼1600 Å) based on the Sérsic model, and analyse the size-luminosity relation as a function of wavelength. Remarkably, the data quality of the NIRCam imaging is sufficient to probe the half-light radius r e down to ∼100 pc at z > 7. Given the limited sample size and magnitude range, we first fix the slope to that observed for larger samples in rest-frame UV using Hubble Space Telescope samples. The median size r 0 at the reference luminosity M = −21 decreases slightly from rest-frame optical (600 ± 80 pc) to UV (450 ± 130 pc). We then refit the size-luminosity relation allowing the slope to vary. The slope is consistent with β ∼ 0.2 for all bands except F150W, where we find a marginally steeper slope of β = 0.53 ± 0.15. The steep UV slope is mainly driven by the smallest and faintest galaxies. If confirmed by larger samples, it implies that the UV size-luminosity relation breaks toward the faint end, as suggested by lensing studies.
AB - We present the first rest-frame optical size-luminosity relation of galaxies at z > 7, using the NIRCam imaging data obtained by the GLASS James Webb Space Telescope Early Release Science (GLASS-JWST-ERS) program, providing the deepest extragalactic data of the ERS campaign. Our sample consists of 19 photometrically selected bright galaxies with m F444W ≤ 27.8 at 7 < z < 9 and m F444W < 28.2 at z ∼ 9−15. We measure the size of the galaxies in five bands, from rest-frame optical (∼4800 Å) to the UV (∼1600 Å) based on the Sérsic model, and analyse the size-luminosity relation as a function of wavelength. Remarkably, the data quality of the NIRCam imaging is sufficient to probe the half-light radius r e down to ∼100 pc at z > 7. Given the limited sample size and magnitude range, we first fix the slope to that observed for larger samples in rest-frame UV using Hubble Space Telescope samples. The median size r 0 at the reference luminosity M = −21 decreases slightly from rest-frame optical (600 ± 80 pc) to UV (450 ± 130 pc). We then refit the size-luminosity relation allowing the slope to vary. The slope is consistent with β ∼ 0.2 for all bands except F150W, where we find a marginally steeper slope of β = 0.53 ± 0.15. The steep UV slope is mainly driven by the smallest and faintest galaxies. If confirmed by larger samples, it implies that the UV size-luminosity relation breaks toward the faint end, as suggested by lensing studies.
KW - Galaxy evolution
UR - https://www.scopus.com/pages/publications/85141329518
U2 - 10.3847/2041-8213/ac8803
DO - 10.3847/2041-8213/ac8803
M3 - Article
AN - SCOPUS:85141329518
SN - 2041-8205
VL - 938
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
IS - 2
M1 - L17
ER -