Abstract
Giant star-forming clumps are a prominent feature of star-forming galaxies (SFGs) and contain important clues on galaxy formation and evolution. However, the basic demographics of clumps and their host galaxies remain uncertain. Using the Hubble Space Telescope/Wide Field Camera 3 F275W images from the Ultraviolet Imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey, we detect and analyze giant star-forming clumps in galaxies at 0.5 ≤ z ≤ 1, connecting two epochs when clumps are common (at cosmic high noon, z ∼ 2) and rare (in the local Universe). We construct a clump sample whose rest-frame 1600 Å luminosity is 3 times higher than the most luminous local H ii regions (M UV ≤ −16 AB). In our sample, 35% ± 3% of low-mass galaxies (log[M ∗/M ⊙] < 10) are clumpy (i.e., containing at least one off-center clump). This fraction changes to 22% ± 3% and 22% ± 4% for intermediate (10 ≤ log[M ∗/M ⊙] ≤ 10.5) and high-mass (log[M ∗/M ⊙] > 10.5) galaxies, in agreement with previous studies. When compared to similar-mass nonclumpy SFGs, low- and intermediate-mass clumpy SFGs tend to have higher star formation rates (SFRs) and bluer rest-frame U − V colors, while high-mass clumpy SFGs tend to be larger than nonclumpy SFGs. However, clumpy and nonclumpy SFGs have similar Sérsic index, indicating a similar underlying density profile. Furthermore, we investigate how the UV luminosity of star-forming regions correlates with the physical properties of host galaxies. On average, more luminous star-forming regions reside in more luminous, smaller, and/or higher specific SFR galaxies and are found closer to their hosts’ galactic centers.
Original language | American English |
---|---|
Article number | 106 |
Journal | Astrophysical Journal |
Volume | 955 |
Issue number | 2 |
DOIs | |
State | Published - 1 Oct 2023 |
Bibliographical note
Funding Information:This work is based on observations with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. Support for program numbers HST-GO-15647 and HST-AR-15798 was provided through a grant from the STScI under NASA contract NAS5-26555.
Funding Information:
D.C. is a Ramon-Cajal Researcher and is supported by the Ministerio de Ciencia, Innovación y Universidades (MICIU/FEDER) under research grant No. PGC2018-094975-C21.
Funding Information:
Y.S.D. acknowledges the support from National Key R&D Program of China for grant No. 2022YFA1605300, and the NSFC grant Nos. 12273051 and 11933003.
Funding Information:
This work is based on observations with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. Support for program numbers HST-GO-15647 and HST-AR-15798 was provided through a grant from the STScI under NASA contract NAS5-26555.
Publisher Copyright:
© 2023. The Author(s). Published by the American Astronomical Society.