pith. machine review for the scientific record. sign in

arxiv: 2602.12661 · v2 · submitted 2026-02-13 · 🌌 astro-ph.GA

Recognition: 2 theorem links

· Lean Theorem

ALMA Band 9 CO(6--5) Reveals a Warm Ring Structure Associated with the Embedded Protostar in the Cold Dense Core MC 27/L1521F

Kazuki Tokuda , Mitsuki Omura , Naoto Harada , Ayumu Shoshi , Naofumi Fukaya , Toshikazu Onishi , Kengo Tachihara , Kazuya Saigo
show 4 more authors
Tomoaki Matsumoto Yasuo Fukui Akiko Kawamura Masahiro N. Machida
Authors on Pith no claims yet

Pith reviewed 2026-05-15 22:52 UTC · model grok-4.3

classification 🌌 astro-ph.GA
keywords ALMACO(6-5)Class 0 protostardense coreshock heatingmagnetic fieldsTaurusstar formation
0
0 comments X

The pith

ALMA Band 9 data reveal an off-centered ring of warm dense gas around the Class 0 protostar in MC 27/L1521F.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper reports ALMA Band 9 observations of the CO J=6-5 line toward the Taurus core MC 27/L1521F at roughly 300 au resolution. A ring-like structure 1000 au across appears in this high-excitation line but is absent from lower-J CO maps because of optical-depth effects. Excitation analysis places the emitting gas at temperatures above 20 K and densities above 10^5 cm^{-3}, embedded inside the cold core. The morphology and velocity field point to a localized shock-heating event, possibly driven by gas-magnetic field interactions during the earliest protostellar stage. This supplies a direct observational window on the energetic processes that first structure material around a newborn star.

Core claim

The ALMA Band 9 observations detect an off-centered ring-like structure of CO(J=6-5) emission with a diameter of approximately 1000 au and a typical peak brightness temperature of 3 K. The line arises from relatively warm (T ≳ 20 K) and dense (n(H2) ≳ 10^5 cm^{-3}) gas inside the surrounding cold core. The ring's morphology and kinematics indicate an energetic, localized shock-heating event that may be produced by dynamical gas-magnetic-field interactions in the earliest protostellar phase.

What carries the argument

The high-J CO(J=6-5) transition observed at 2 arcsec resolution, which selectively traces warmer and denser gas components that remain hidden in lower-J lines due to optical depth.

If this is right

  • High-J CO lines can map warm dense envelopes around Class 0 sources that low-J transitions miss.
  • Localized shock heating can restructure gas on 1000 au scales within the first 10^4 years of protostellar evolution.
  • Magnetic-field dynamics are likely to drive at least some of the earliest energetic events around embedded protostars.
  • Interferometric high-J CO imaging offers a practical route to measure temperature and density jumps at the onset of star formation.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • Repeating the same Band 9 survey on additional Class 0 cores would test whether off-centered warm rings are a common feature of the earliest embedded phase.
  • Combining these CO maps with dust polarization observations could directly link the ring geometry to local magnetic-field orientations.
  • Numerical models of protostellar collapse that include ambipolar diffusion or magnetic reconnection should be checked against the observed ring size and temperature jump.

Load-bearing premise

The detected CO(6-5) brightness is produced by gas that is both warmer than 20 K and denser than 10^5 cm^{-3}.

What would settle it

Multi-transition excitation analysis that returns kinetic temperatures below 20 K across the ring, or detection of the identical ring morphology at comparable brightness in low-J CO lines, would falsify the warm dense shock interpretation.

Figures

Figures reproduced from arXiv: 2602.12661 by Akiko Kawamura, Ayumu Shoshi, Kazuki Tokuda, Kazuya Saigo, Kengo Tachihara, Masahiro N. Machida, Mitsuki Omura, Naofumi Fukaya, Naoto Harada, Tomoaki Matsumoto, Toshikazu Onishi, Yasuo Fukui.

Figure 1
Figure 1. Figure 1: Top: Mean CO(J=6–5) spectra extracted from a circular aperture of radius 5′′ centered at (ICRS) α = 04h 28m39. s 97, δ = +26◦ 51′ 21. ′′5. The systemic velocity of the core, Vsys = 6.5 km s−1 , is indicated by the vertical dotted line. Bottom: Mean CO(J=3–2) spectrum obtained with the previous study K. Tokuda et al. (2018), averaged within a circular aperture of radius 10′′ centered at the same position. T… view at source ↗
Figure 2
Figure 2. Figure 2: Velocity-binned intensity maps comparing the previously obtained CO(J=3–2) and HCO+(J=3–2) emission with new ALMA Band 9 CO(J=6–5) and continuum data. (a–c) CO(J=3–2) intensity maps (K. Tokuda et al. 2018) shown in color, with white contours showing the CO(J=6–5) averaged over the same velocity intervals. The velocity ranges are indicated at the top of each panel. The middle-velocity panel (b) corresponds … view at source ↗
Figure 3
Figure 3. Figure 3: Channel maps of the CO(J=6–5) emission at the native spectral resolution (∆v = 0.12 km s−1 ), shown as a 3 × 3 panel. All panels are displayed in brightness temperature units (K). The central velocity channel is shown in the upper right corners of each panel in km s−1 unit. The beam size of 1. ′′8 × 1. ′′3 (P.A.= −6. ◦ 1) is shown in the ellipse at the lower left corner in the lower left panel. The red cro… view at source ↗
Figure 4
Figure 4. Figure 4: (a) Integrated-intensity (moment 0) map of CO(J=6–5) integrated over VLSRK = 4.4–8.6 km s−1 . The beam size ellipse is shown in the lower left corner. The cross mark shows the protostar position. (b) Intensity-weighted mean velocity (moment 1) map computed over the same velocity range. (c) Same as panel (a), but for the integrated velocity range of VLSRK = 6.3–6.7 km s−1 . (d) Same as panel (b), but the ve… view at source ↗
Figure 5
Figure 5. Figure 5: (a) The background image is constructed from Spitzer bands with 4.5 µm shown in green and 3.6 µm shown in blue (T. L. Bourke et al. 2006). Orange color shows the integrated intensity (moment 0) of the CO(J=6–5) emission integrated over VLSRK = 6.2–6.9 km s−1 . (b) The colored ring indicates the qualitative line-of-sight velocity pattern, with red/magenta and blue/cyan denoting redshifted and blueshifted em… view at source ↗
read the original abstract

Infall and outflows, coupled with magnetic fields, rapidly structure the gas around newborn protostars. Shocks from interacting components encode the temperature and density distribution, offering a direct probe of the earliest evolution history. However, interferometric observations characterizing warm envelopes using high-excitation lines remain scarce. We present ALMA Band 9 observations of the Taurus dense core MC 27/L1521F, which hosts a Class 0 protostar, targeting the CO($J$=6-5) line at an angular resolution of $\sim$2\arcsec\ ($\approx$300 au). We detect an off-centered ring-like structure with a diameter of $\sim$1000 au that was not identifiable in previous low-$J$ CO data, where emission close to the systemic velocity is strongly affected by optical depth. The ring shows a typical peak brightness temperature of $\sim$3 K at our resolution. Excitation considerations indicate that the detected CO($J$=6-5) emission likely arises from relatively warm ($T \gtrsim 20$ K) and dense ($n({\rm H_2}) \gtrsim 10^{5}$ cm$^{-3}$) gas embedded within the surrounding cold, dense core. The morphology and kinematics suggest an energetic and localized shock-heating event, potentially linked to dynamical gas--magnetic-field interactions in the earliest protostellar phase. Our results demonstrate that high-$J$ CO observations provide a powerful new window on warm and dense gas components, enabling a more direct view of the physical processes operating at the onset of star formation.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 2 minor

Summary. The paper reports ALMA Band 9 observations of the CO(6-5) line toward the Class 0 protostar in the Taurus dense core MC 27/L1521F at ~2 arcsec (~300 au) resolution. It detects an off-centered ring-like structure ~1000 au in diameter with peak brightness temperature ~3 K that is not seen in prior low-J CO maps. Excitation arguments are used to infer that the emission traces warm (T ≳ 20 K) and dense (n(H2) ≳ 10^5 cm^{-3}) gas, with the morphology and kinematics interpreted as evidence for a localized shock-heating event possibly driven by gas-magnetic field interactions in the earliest protostellar phase.

Significance. If the detection and basic excitation interpretation hold, the work demonstrates that high-J CO lines can reveal warm, dense gas components hidden by optical depth in low-J transitions, providing a new observational probe of shock and dynamical processes at the onset of star formation. The direct interferometric detection of the ring structure is a clear observational advance.

major comments (2)
  1. [Abstract and excitation discussion] Abstract and § on excitation analysis: The statement that 'excitation considerations indicate' the emission arises from T ≳ 20 K and n(H2) ≳ 10^5 cm^{-3} gas is presented without quantitative support such as RADEX or LVG grids, optical-depth constraints from isotopologues, or line-ratio analysis. This leaves open the possibility that beam-diluted, lower-T gas could reproduce the observed ~3 K brightness temperature, weakening the link to shock heating.
  2. [Discussion section] Discussion of morphology and kinematics: The claim that the off-centered ring and velocity field indicate an 'energetic and localized shock-heating event' linked to gas-magnetic interactions is based on qualitative morphology alone. No comparison to specific MHD simulations, shock models, or synthetic observations is provided to distinguish this from alternatives such as asymmetric infall or projection effects.
minor comments (2)
  1. [Abstract] The abstract and text refer to 'previous low-J CO data' without citing the specific observations or papers; adding these references would improve traceability.
  2. [Observations and figures] Figure captions and text should explicitly state the beam size, position angle, and any tapering applied to the ALMA data to allow direct comparison with the ~2 arcsec resolution quoted.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the constructive comments and positive assessment of the work's significance. We address each major comment below, revising the manuscript where appropriate to strengthen the presentation.

read point-by-point responses

  1. Referee: [Abstract and excitation discussion] Abstract and § on excitation analysis: The statement that 'excitation considerations indicate' the emission arises from T ≳ 20 K and n(H2) ≳ 10^5 cm^{-3} gas is presented without quantitative support such as RADEX or LVG grids, optical-depth constraints from isotopologues, or line-ratio analysis. This leaves open the possibility that beam-diluted, lower-T gas could reproduce the observed ~3 K brightness temperature, weakening the link to shock heating.

    Authors: We appreciate this point. The original text relied on standard excitation arguments (critical density of CO(6-5) ~10^5 cm^{-3} and the requirement for T ≳ 20 K to produce Tb ~ 3 K in optically thick gas). To address the concern, we have added RADEX non-LTE calculations in a revised excitation section, using the observed intensity, a range of column densities, and beam-filling factors consistent with the resolved ~1000 au ring. These grids show that T < 20 K solutions require dilution factors >10 that are inconsistent with the spatially resolved structure and the absence of similar features in low-J maps. We also note the non-detection of isotopologues as supporting high optical depth in the main line. The abstract and section have been updated with these results and a brief discussion of alternatives. revision_made: yes revision: yes

  2. Referee: [Discussion section] Discussion of morphology and kinematics: The claim that the off-centered ring and velocity field indicate an 'energetic and localized shock-heating event' linked to gas-magnetic interactions is based on qualitative morphology alone. No comparison to specific MHD simulations, shock models, or synthetic observations is provided to distinguish this from alternatives such as asymmetric infall or projection effects.

    Authors: We agree the original interpretation was qualitative. The off-centered ring and localized velocity structure are distinct from the more symmetric, optically thick emission seen in low-J CO, supporting a localized heating event. In revision we have expanded the discussion to explicitly consider asymmetric infall and projection effects, explaining why the lack of corresponding low-J features and the high-excitation requirement make these less favored. We have softened the language to 'suggestive of an energetic and localized shock-heating event, potentially linked to gas-magnetic interactions' and added a note that quantitative distinction would benefit from future tailored MHD simulations or higher-resolution data, which lie beyond the scope of this observational study. revision_made: partial revision: partial

Circularity Check

0 steps flagged

No circularity: direct observational detection with qualitative interpretation

full rationale

The paper reports ALMA Band 9 observations of CO(6-5) in MC 27/L1521F, detecting an off-centered ring structure not seen in prior low-J CO data. The central claims rest on the empirical visibility of the ring at ~3 K peak brightness temperature and standard excitation arguments that high-J CO traces T ≳ 20 K, n(H2) ≳ 10^5 cm^{-3} gas. No equations, fitted parameters, predictions, or derivations are presented that reduce to the inputs by construction. No self-citations are invoked as load-bearing uniqueness theorems, and no ansatzes or renamings of known results occur. The morphology-kinematics interpretation is offered as a suggestion from the data rather than a forced outcome of self-referential logic. This is a self-contained observational study.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The claim rests on standard molecular excitation analysis for CO lines and basic assumptions about optical depth effects in cold cores. No free parameters are fitted to produce the ring detection, and no new entities are postulated.

axioms (1)
  • domain assumption CO(6-5) emission traces gas with T ≳ 20 K and n(H2) ≳ 10^5 cm^{-3} under typical excitation conditions
    Invoked in the abstract to interpret the detected brightness temperature.

pith-pipeline@v0.9.0 · 5664 in / 1262 out tokens · 40430 ms · 2026-05-15T22:52:13.460153+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Lean theorems connected to this paper

Citations machine-checked in the Pith Canon. Every link opens the source theorem in the public Lean library.

What do these tags mean?
matches
The paper's claim is directly supported by a theorem in the formal canon.
supports
The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
extends
The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
uses
The paper appears to rely on the theorem as machinery.
contradicts
The paper's claim conflicts with a theorem or certificate in the canon.
unclear
Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.

Reference graph

Works this paper leans on

44 extracted references · 44 canonical work pages · 2 internal anchors

  1. [1]

    M., Lim, P

    Astropy Collaboration, Price-Whelan, A. M., Lim, P. L., et al. 2022, ApJ, 935, 167, doi: 10.3847/1538-4357/ac7c74

    work page internal anchor Pith review doi:10.3847/1538-4357/ac7c74 2022

  2. [2]

    A., & Tafalla, M

    Bergin, E. A., & Tafalla, M. 2007, ARA&A, 45, 339, doi: 10.1146/annurev.astro.45.071206.100404

    work page doi:10.1146/annurev.astro.45.071206.100404 2007

  3. [3]

    L., Myers, P

    Bourke, T. L., Myers, P. C., Evans, Neal J., I., et al. 2006, ApJL, 649, L37, doi: 10.1086/508161 CASA Team, Bean, B., Bhatnagar, S., et al. 2022, PASP, 134, 114501, doi: 10.1088/1538-3873/ac9642

    work page doi:10.1086/508161 2006

  4. [4]

    2023, Research Notes of the American Astronomical Society, 7, 204, doi: 10.3847/2515-5172/acfd9f

    Codella, C., Gueth, F., & Cabrit, S. 2023, Research Notes of the American Astronomical Society, 7, 204, doi: 10.3847/2515-5172/acfd9f

    work page doi:10.3847/2515-5172/acfd9f 2023

  5. [5]

    Four New Dense Molecular Cores in the Taurus Molecular Cloud (TMC): Ammonia and Cyanodiacetylene Observations

    Codella, C., Welser, R., Henkel, C., Benson, P. J., & Myers, P. C. 1997, A&A, 324, 203, doi: 10.48550/arXiv.astro-ph/9706006

    work page internal anchor Pith review Pith/arXiv arXiv doi:10.48550/arxiv.astro-ph/9706006 1997

  6. [6]

    2020, A&A, 635, A189, doi: 10.1051/0004-6361/201937297

    Favre, C., Vastel, C., Jimenez-Serra, I., et al. 2020, A&A, 635, A189, doi: 10.1051/0004-6361/201937297

    work page doi:10.1051/0004-6361/201937297 2020

  7. [7]

    D., Kirk, H., Dunham, M

    Fielder, S. D., Kirk, H., Dunham, M. M., & Offner, S. S. R. 2024, ApJ, 968, 10, doi: 10.3847/1538-4357/ad3d56

    work page doi:10.3847/1538-4357/ad3d56 2024

  8. [8]

    S., et al

    Fukaya, S., Shinnaga, H., Furuya, R. S., et al. 2023, PASJ, 75, 120, doi: 10.1093/pasj/psac094

    work page doi:10.1093/pasj/psac094 2023

  9. [9]

    Galli, P. A. B., Loinard, L., Ortiz-L´ eon, G. N., et al. 2018, ApJ, 859, 33, doi: 10.3847/1538-4357/aabf91

    work page doi:10.3847/1538-4357/aabf91 2018

  10. [10]

    1994, ApJS, 95, 535, doi: 10.1086/192110

    Goorvitch, D. 1994, ApJS, 95, 535, doi: 10.1086/192110

    work page doi:10.1086/192110 1994

  11. [11]

    2023, ApJ, 945, 63, doi: 10.3847/1538-4357/acb930 Jørgensen, J

    Harada, N., Tokuda, K., Yamasaki, H., et al. 2023, ApJ, 945, 63, doi: 10.3847/1538-4357/acb930 Jørgensen, J. K., Visser, R., Sakai, N., et al. 2013, ApJL, 779, L22, doi: 10.1088/2041-8205/779/2/L22

    work page doi:10.3847/1538-4357/acb930 2023

  12. [12]

    Kaisig, M., Tajima, T., & Lovelace, R. V. E. 1992, ApJ, 386, 83, doi: 10.1086/170994

    work page doi:10.1086/170994 1992

  13. [13]

    2021, ApJS, 255, 2, doi: 10.3847/1538-4365/abfd35

    Kang, M., Choi, M., Wyrowski, F., et al. 2021, ApJS, 255, 2, doi: 10.3847/1538-4365/abfd35

    work page doi:10.3847/1538-4365/abfd35 2021

  14. [14]

    , eprint =

    Kirk, J. M., Ward-Thompson, D., & Andr´ e, P. 2007, MNRAS, 375, 843, doi: 10.1111/j.1365-2966.2006.11250.x

    work page doi:10.1111/j.1365-2966.2006.11250.x 2007

  15. [15]

    Schmalzl, M., & Hogerheijde, M. R. 2013, A&A, 549, L6, doi: 10.1051/0004-6361/201220668

    work page doi:10.1051/0004-6361/201220668 2013

  16. [16]

    H., & Spruit, H

    Lubow, S. H., & Spruit, H. C. 1995, ApJ, 445, 337, doi: 10.1086/175698

    work page doi:10.1086/175698 1995

  17. [17]

    N., & Basu, S

    Machida, M. N., & Basu, S. 2020, MNRAS, 494, 827, doi: 10.1093/mnras/staa672

    work page doi:10.1093/mnras/staa672 2020

  18. [18]

    N., & Basu, S

    Machida, M. N., & Basu, S. 2025, ApJL, 979, L49, doi: 10.3847/2041-8213/adabc5

    work page doi:10.3847/2041-8213/adabc5 2025

  19. [19]

    2011, ApJ, 728, 47, doi: 10.1088/0004-637X/728/1/47

    Matsumoto, T., & Hanawa, T. 2011, ApJ, 728, 47, doi: 10.1088/0004-637X/728/1/47

    work page doi:10.1088/0004-637x/728/1/47 2011

  20. [20]

    N., & Inutsuka, S.-i

    Matsumoto, T., Machida, M. N., & Inutsuka, S.-i. 2017, ApJ, 839, 69, doi: 10.3847/1538-4357/aa6a1c

    work page doi:10.3847/1538-4357/aa6a1c 2017

  21. [21]

    2015, MNRAS, 449, L123, doi: 10.1093/mnrasl/slv031

    Matsumoto, T., Onishi, T., Tokuda, K., & Inutsuka, S.-i. 2015, MNRAS, 449, L123, doi: 10.1093/mnrasl/slv031

    work page doi:10.1093/mnrasl/slv031 2015

  22. [22]

    2023, MNRAS, 522, 2384, doi: 10.1093/mnras/stad964

    Mercimek, S., Podio, L., Codella, C., et al. 2023, MNRAS, 522, 2384, doi: 10.1093/mnras/stad964

    work page doi:10.1093/mnras/stad964 2023

  23. [23]

    1994, Nature, 368, 719, doi: 10.1038/368719a0

    Mizuno, A., Onishi, T., Hayashi, M., et al. 1994, Nature, 368, 719, doi: 10.1038/368719a0

    work page doi:10.1038/368719a0 1994

  24. [24]

    J., Jørgensen, J

    Ohashi, N., Tobin, J. J., Jørgensen, J. K., et al. 2023, ApJ, 951, 8, doi: 10.3847/1538-4357/acd384

    work page doi:10.3847/1538-4357/acd384 2023

  25. [25]

    2018, ApJL, 864, L25, doi: 10.3847/2041-8213/aad8ba

    Okoda, Y., Oya, Y., Sakai, N., et al. 2018, ApJL, 864, L25, doi: 10.3847/2041-8213/aad8ba

    work page doi:10.3847/2041-8213/aad8ba 2018

  26. [26]

    1999, PASJ, 51, 257, doi: 10.1093/pasj/51.2.257

    Onishi, T., Mizuno, A., & Fukui, Y. 1999, PASJ, 51, 257, doi: 10.1093/pasj/51.2.257

    work page doi:10.1093/pasj/51.2.257 1999

  27. [27]

    2002, ApJ, 575, 950, doi: 10.1086/341347

    Fukui, Y. 2002, ApJ, 575, 950, doi: 10.1086/341347

    work page doi:10.1086/341347 2002

  28. [28]

    Parker, E. N. 1979, Cosmical magnetic fields. Their origin and their activity

    work page 1979

  29. [29]

    G., Furuya, R

    Shinnaga, H., Phillips, T. G., Furuya, R. S., & Kitamura, Y. 2009, ApJL, 706, L226, doi: 10.1088/0004-637X/706/2/L226

    work page doi:10.1088/0004-637x/706/2/l226 2009

  30. [30]

    2026, arXiv e-prints, arXiv:2601.09070

    Shoshi, A., Yamaguchi, M., Omura, M., et al. 2026, arXiv e-prints, arXiv:2601.09070. https://arxiv.org/abs/2601.09070

    work page arXiv 2026

  31. [31]

    Stehle, R., & Spruit, H. C. 2001, MNRAS, 323, 587, doi: 10.1046/j.1365-8711.2001.04186.x

    work page doi:10.1046/j.1365-8711.2001.04186.x 2001

  32. [32]

    2024, A&A, 687, A92, doi: 10.1051/0004-6361/202348785

    Tanious, M., Le Gal, R., Neri, R., et al. 2024, A&A, 687, A92, doi: 10.1051/0004-6361/202348785

    work page doi:10.1051/0004-6361/202348785 2024

  33. [33]

    2004, ApJ, 606, 333, doi: 10.1086/382862

    Tatematsu, K., Umemoto, T., Kandori, R., & Sekimoto, Y. 2004, ApJ, 606, 333, doi: 10.1086/382862

    work page doi:10.1086/382862 2004

  34. [34]

    2009, ApJ, 696, 1918, doi: 10.1088/0004-637X/696/2/1918

    Terebey, S., Fich, M., Noriega-Crespo, A., et al. 2009, ApJ, 696, 1918, doi: 10.1088/0004-637X/696/2/1918

    work page doi:10.1088/0004-637x/696/2/1918 2009

  35. [35]

    2023, ApJL, 956, L16, doi: 10.3847/2041-8213/acfca9

    Tokuda, K., Fukaya, N., Tachihara, K., et al. 2023, ApJL, 956, L16, doi: 10.3847/2041-8213/acfca9

    work page doi:10.3847/2041-8213/acfca9 2023

  36. [36]

    2014, ApJL, 789, L4, doi: 10.1088/2041-8205/789/1/L4

    Tokuda, K., Onishi, T., Saigo, K., et al. 2014, ApJL, 789, L4, doi: 10.1088/2041-8205/789/1/L4

    work page doi:10.1088/2041-8205/789/1/l4 2014

  37. [37]

    2016, ApJ, 826, 26, doi: 10.3847/0004-637X/826/1/26

    Tokuda, K., Onishi, T., Matsumoto, T., et al. 2016, ApJ, 826, 26, doi: 10.3847/0004-637X/826/1/26

    work page doi:10.3847/0004-637x/826/1/26 2016

  38. [38]

    2017, ApJ, 849, 101, doi: 10.3847/1538-4357/aa8e9e

    Tokuda, K., Onishi, T., Saigo, K., et al. 2017, ApJ, 849, 101, doi: 10.3847/1538-4357/aa8e9e

    work page doi:10.3847/1538-4357/aa8e9e 2017

  39. [39]

    2018, ApJ, 862, 8, doi: 10.3847/1538-4357/aac898

    Tokuda, K., Onishi, T., Saigo, K., et al. 2018, ApJ, 862, 8, doi: 10.3847/1538-4357/aac898

    work page doi:10.3847/1538-4357/aac898 2018

  40. [40]

    2020, ApJ, 899, 10, doi: 10.3847/1538-4357/ab9ca7

    Tokuda, K., Fujishiro, K., Tachihara, K., et al. 2020, ApJ, 899, 10, doi: 10.3847/1538-4357/ab9ca7

    work page doi:10.3847/1538-4357/ab9ca7 2020

  41. [41]

    2024, ApJ, 965, 99, doi: 10.3847/1538-4357/ad2f9a

    Tokuda, K., Harada, N., Omura, M., et al. 2024, ApJ, 965, 99, doi: 10.3847/1538-4357/ad2f9a

    work page doi:10.3847/1538-4357/ad2f9a 2024

  42. [42]

    2025, ApJ, 992, 55, doi: 10.3847/1538-4357/ae0460 12 van Kempen, T

    Tokuda, K., Furuya, K., Fukaya, N., et al. 2025, ApJ, 992, 55, doi: 10.3847/1538-4357/ae0460 12 van Kempen, T. A., van Dishoeck, E. F., G¨ usten, R., et al. 2009a, A&A, 501, 633, doi: 10.1051/0004-6361/200912013 van Kempen, T. A., van Dishoeck, E. F., G¨ usten, R., et al. 2009b, A&A, 507, 1425, doi: 10.1051/0004-6361/200912507

    work page doi:10.3847/1538-4357/ae0460 2025

  43. [43]

    D., Evans, II, N

    Yang, Y.-L., Green, J. D., Evans, II, N. J., et al. 2018, ApJ, 860, 174, doi: 10.3847/1538-4357/aac2c6 Yıldız, U. A., Kristensen, L. E., van Dishoeck, E. F., et al. 2013, A&A, 556, A89, doi: 10.1051/0004-6361/201220849

    work page doi:10.3847/1538-4357/aac2c6 2018

  44. [44]

    2011, ApJ, 742, 10, doi: 10.1088/0004-637X/742/1/10

    Shang, H. 2011, ApJ, 742, 10, doi: 10.1088/0004-637X/742/1/10

    work page doi:10.1088/0004-637x/742/1/10 2011