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Published August 10, 2025 | Version Published
Journal Article Open

ALMA Lensing Cluster Survey: Physical Characterization of Near-infrared-dark Intrinsically Faint ALMA Sources at z = 2–4

Creators

  • 1. ROR icon University of Tokyo
  • 2. ROR icon National Astronomical Observatory of Japan
  • 3. ROR icon Nagoya University
  • 4. ROR icon Chiba University
  • 5. ROR icon Hokkai Gakuen University
  • 6. ROR icon Durham University
  • 7. ROR icon California Institute of Technology
  • 8. ROR icon Institute of Astronomy and Astrophysics, Academia Sinica
  • 9. ROR icon National Central University
  • 10. ROR icon Harvard-Smithsonian Center for Astrophysics
  • 11. ROR icon University of Arizona
  • 12. ROR icon The University of Texas at Austin
  • 13. ROR icon University of Copenhagen
  • 14. ROR icon Ministry of Education of the People's Republic of China
  • 15. ROR icon Kyoto University
  • 16. ROR icon University of Granada
  • 17. ROR icon European Southern Observatory
  • 18. ROR icon Chinese Academy of Sciences
  • 19. ROR icon University of Science and Technology of China
  • 20. ROR icon Pontificia Universidad Católica de Chile
  • 21. ROR icon Millennium Institute of Astrophysics
  • 22. ROR icon The Graduate University for Advanced Studies, SOKENDAI
  • 23. ROR icon Space Telescope Science Institute
  • 24. ROR icon University of Geneva
  • 25. ROR icon Research Institute in Astrophysics and Planetology
  • 26. ROR icon International Centre for Radio Astronomy Research
  • 27. ROR icon Centre of Excellence for All-Sky Astrophysics
  • 28. ROR icon University of Groningen
  • 29. ROR icon Diego Portales University
  • 30. ROR icon Las Campanas Observatory
  • 31. ROR icon Chalmers University of Technology
  • 32. ROR icon Max Planck Institute for Extraterrestrial Physics
  • 33. ROR icon Technical University of Denmark
  • 34. ROR icon Kavli Institute for the Physics and Mathematics of the Universe
  • 35. ROR icon Johns Hopkins University
  • 36. ROR icon Ben-Gurion University of the Negev

Abstract

We present results from Atacama Large Millimeter/submillimeter Array (ALMA) spectral line-scan observations at 3 mm and 2 mm bands of three near-infrared-dark (NIR-dark) galaxies behind two massive lensing clusters MACS J0417.5-1154 and RXC J0032.1+1808. Each of these three sources is a (sub)millimeter faint (delensed S 1.2 mm < 1 mJy) triply lensed system originally discovered in the ALMA Lensing Cluster Survey. We have successfully detected CO and [C i] emission lines and confirmed that their spectroscopic redshifts are z = 3.652, 2.391, and 2.985. By utilizing a rich multiwavelength data set, we find that the NIR-dark galaxies are located on the star formation main sequence in the intrinsic stellar mass range of log (M */M ⊙) = 9.8–10.4, which is about 1 order of magnitude lower than that of typical submillimeter galaxies (SMGs). These NIR-dark galaxies show a variety in gas depletion times and spatial extent of dust emission. One of the three is a normal star-forming galaxy with gas depletion time consistent with a scaling relation, and its infrared surface brightness is an order of magnitude smaller than that of typical SMGs. Since this galaxy has an elongated axis ratio of ∼0.17, we argue that normal star-forming galaxies in an edge-on configuration can be heavily dust-obscured. This implies that existing deep WFC3/F160W surveys may miss a fraction of typical star-forming main-sequence galaxies due to their edge-on orientation.

Copyright and License

© 2025. The Author(s). Published by the American Astronomical Society.

Acknowledgement

We thank Masato Hagimoto for providing us with the [C i](1–0)/CO(4–3)/FIR data. We appreciate Takeo Minezaki for constructive comments and suggestions. We also sincerely thank the anonymous referee for constructive comments and suggestions, which have improved the quality of this paper. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2018.1.00035.L, #2019.1.00949.S, and #2021.1.01246.S. ALMA is a partnership of ESO (representing its member states), NSF (USA), and NINS (Japan), together with NRC (Canada), NSTC and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO, and NAOJ. This work is based (in part) on data collected at the Magellan Telescopes, with the support from the ALTA program of ASIAA. Data analysis was in part carried out on the Multi-wavelength Data Analysis System operated by the Astronomy Data Center (ADC), NAOJ. This research was supported by FoPM, WINGS Program, the University of Tokyo. A.T. was supported by the ALMA Japan Research Grant of NAOJ ALMA Project, NAOJ-ALMA-343. A.T. also acknowledges the support by JSPS KAKENHI grant No. 24KJ0562. K.K. acknowledges the support by JSPS KAKENHI grant No. JP17H06130 and JP22H04939, and the NAOJ ALMA Scientific Research grant No. 2017-06B. H.U. appreciates the support by JSPS KAKENHI grant No. 20H01953, 22KK0231, and 23K20240. W.H.W. and Z.K.G. acknowledge support by NSTC grant 111-2112-M-001-052-MY3. F.S. acknowledges JWST/NIRCam contract to the University of Arizona NAS5-02015. R.U. appreciates the support by JSPS KAKENHI grant No. 22J22795. F.E.B. acknowledges support from ANID-Chile BASAL CATA FB210003, FONDECYT Regular 1200495, and Millennium Science Initiative Program—ICN12_009.

Facilities

HST - Hubble Space Telescope satellite (ACS and WFC3), Magellan - :Baade - (FourStar), VLT:Yepun - Very Large Telescope (Yepun) (HAWK-I), Spitzer - Spitzer Space Telescope satellite (IRAC), Herschel - European Space Agency's Herschel space observatory (PACS), JCMT - James Clerk Maxwell Telescope (SCUBA-2), ALMA - Atacama Large Millimeter Array.

Software References

Astropy (Astropy Collaboration et al. 2022), Glafic (M. Oguri 2010), CASA (J. P. McMullin et al. 2007), Photutils (L. Bradley et al. 2022), SExtractor (E. Bertin & S. Arnouts 1996), PSFEx (E. Bertin 2011), CIGALE (M. Boquien et al. 2019), PDRToolbox (M. W. Pound & M. G. Wolfire 2023), Dynesty (J. S. Speagle 2020).

Files

ALMA Lensing Cluster Survey Physical Characterization of Near-infrared-dark Intrinsically Faint ALMA Sources.pdf

Files (14.6 MB)

Additional details

Funding

The University of Tokyo
FoPM
MEXT ∣ Japan Society for the Promotion of Science
17H06130
MEXT ∣ Japan Society for the Promotion of Science
P22H04939
National Astronomical Observatory of Japan
2017-06
MEXT ∣ Japan Society for the Promotion of Science
20H01953
MEXT ∣ Japan Society for the Promotion of Science
22KK0231
MEXT ∣ Japan Society for the Promotion of Science
23K20240
National Science and Technology Council
111- 2112-M-001-052-MY3
University of Arizona
AS5-02015
MEXT ∣ Japan Society for the Promotion of Science
22J22795
MEXT ∣ Japan Society for the Promotion of Science
24KJ0562
ANID ∣ Fondo Nacional de Desarrollo Científico y Tecnológico
1200495
Millennium Science Initiative Program
ICN12_009
ALMA Japan Research Grant
NAOJ-ALMA-343

Dates

Available
2025-08-07
Published online

Caltech Custom Metadata

Caltech groups
Division of Physics, Mathematics and Astronomy (PMA)
Publication Status
Published