A Diverse Population of z ～ 2 ULIRGs Revealed by JWST Imaging

作者：Huang, J. -S.; Li, Zi-Jian; Cheng, Cheng; Hou, Meicun; Yan, Haojing; Willner, S. P.^*; Dai, Y. -S.; Zheng, X. Z.; Pan, J.; Rigopoulou, D.; Wang, T.; Li, Zhiyuan; Liang, Piaoran; Esamdin, A.; Fazio, G. G.

来源：Astrophysical Journal, 2023, 949(2): 83.

DOI：10.3847/1538-4357/acc9c3

• ULTRALUMINOUS INFRARED GALAXIES
• SPECTRAL ENERGY-DISTRIBUTIONS
• STAR-FORMING GALAXIES
• MAIN-SEQUENCE
• DEEP-FIELD
• EVOLUTION
• SPECTROSCOPY
• REDSHIFTS
• HERSCHEL
• STARBURST

Four ultraluminous infrared galaxies (ULIRGs) observed with JWST/NIRcam in the Cosmos Evolution Early Release Science program offer an unbiased preview of the z & SIM; 2 ULIRG population. The objects were originally selected at 24 & mu;m and have strong polycyclic aromatic hydrocarbon emission features observed with Spitzer/Infrared Spectrometer. The four objects have similar stellar masses of & SIM;10(11) M (& ODOT;) but otherwise are quite diverse. One is an isolated disk galaxy, but it has an active nucleus as shown by X-ray observations and by a bright point-source nucleus. Two others are merging pairs with mass ratios of 6-7:1. One has active nuclei in both components, while the other has only one active nucleus: the one in the less-massive neighbor, not the ULIRG. The fourth object is clumpy and irregular and is probably a merger, but there is no sign of an active nucleus. The intrinsic spectral energy distributions for the four active galactic nuclei in these systems are typical of type-2 QSOs. This study is consistent with the idea that even if internal processes can produce large luminosities at z & SIM; 2, galaxy merging may still be necessary for the most luminous objects. The diversity of these four initial examples suggests that large samples will be needed to understand the z & SIM; 2 ULIRG population.

• 单位
  中国科学院; 南京大学; 北京大学; 桂林理工大学; 中国科学院研究生院