대표연구 논문 실적
ODIN: Rest-frame Optical Morphologies and Star Formation Activity of Lyα Emitters at z=2.4, 3.1, and 4.5
발행년도
20260910
저자
Sang Hyeok Im, Ho Seong Hwang, Jeong Hwan Lee, Robin Ciardullo, Eric Gawiser, Caryl Gronwall, Lucia Guaita, Woong-Seob Jeong, Ankit Kumar, Kyoung-Soo Lee, Changbom Park, Vandana Ramakrishnan, Akriti Singh, Hyunmi Song, Sungryong Hong, Juhan Kim, Jaehyun Lee, Christophe Pichon, Caitlin M. Casey, Maximilien Franco, Santosh Harish, and Jeyhan S. Kartaltepe
저널
ASTROPHYSICAL JOURNAL
작성자
admsnulamp
작성일
2026-09-28
조회
25
Abstract
We analyze the rest-frame optical (similar to 8000 & Aring;) morphologies and star formation activity of Ly alpha emitters (LAEs) at redshifts 2.4, 3.1, and 4.5, identified in the One-hundred-deg2 DECam Imaging in Narrowband (ODIN) survey. To compare their physical properties with those of other galaxies, we construct a comparison sample of typical star-forming galaxies (SFGs) at similar redshifts from the COSMOS2025 catalog. Using James Webb Space Telescope NIRCam images from the COSMOS-Web survey, we measure the rest-frame optical sizes and S & eacute;rsic indices. We first examine their size-mass relations and find that LAEs at all three redshifts have smaller sizes than typical SFGs, with the size difference decreasing at higher redshifts. We also find that LAEs tend to have larger S & eacute;rsic indices at z = 2.4 and 3.1 than typical SFGs, but the difference becomes weaker at z = 4.5. These trends are qualitatively reproduced in the Horizon Run 5 cosmological hydrodynamical simulation. We then investigate star formation activity and find that LAEs exhibit higher star formation rates (SFRs) than typical SFGs at all redshifts considered. Finally, we examine the connection between Ly alpha emission and galaxy structure, finding that the rest-frame equivalent width (REW) of the Ly alpha emission line is negatively and positively correlated with size and S & eacute;rsic index, respectively. In addition, we find a strong positive correlation between Ly alpha REW and the ratio of the instantaneous SFR to that averaged over the last 100 Myr (i.e., SFRinst/SFR100Myr). These results suggest the compact and starbursting nature of LAEs, and provide important constraints on the physical mechanisms responsible for Ly alpha photon escape from galaxies.
DOI: http://dx.doi.org/10.3847/1538-4357/ae990e
We analyze the rest-frame optical (similar to 8000 & Aring;) morphologies and star formation activity of Ly alpha emitters (LAEs) at redshifts 2.4, 3.1, and 4.5, identified in the One-hundred-deg2 DECam Imaging in Narrowband (ODIN) survey. To compare their physical properties with those of other galaxies, we construct a comparison sample of typical star-forming galaxies (SFGs) at similar redshifts from the COSMOS2025 catalog. Using James Webb Space Telescope NIRCam images from the COSMOS-Web survey, we measure the rest-frame optical sizes and S & eacute;rsic indices. We first examine their size-mass relations and find that LAEs at all three redshifts have smaller sizes than typical SFGs, with the size difference decreasing at higher redshifts. We also find that LAEs tend to have larger S & eacute;rsic indices at z = 2.4 and 3.1 than typical SFGs, but the difference becomes weaker at z = 4.5. These trends are qualitatively reproduced in the Horizon Run 5 cosmological hydrodynamical simulation. We then investigate star formation activity and find that LAEs exhibit higher star formation rates (SFRs) than typical SFGs at all redshifts considered. Finally, we examine the connection between Ly alpha emission and galaxy structure, finding that the rest-frame equivalent width (REW) of the Ly alpha emission line is negatively and positively correlated with size and S & eacute;rsic index, respectively. In addition, we find a strong positive correlation between Ly alpha REW and the ratio of the instantaneous SFR to that averaged over the last 100 Myr (i.e., SFRinst/SFR100Myr). These results suggest the compact and starbursting nature of LAEs, and provide important constraints on the physical mechanisms responsible for Ly alpha photon escape from galaxies.
DOI: http://dx.doi.org/10.3847/1538-4357/ae990e
