The Dense Gas Structures Around MMS 2/OMC-3 Traced by C18O Emission
Abstract
We report the Atacama Large Millimeter/submillimeter Array observations of 1.3 mm continuum, C18O (J=2−$1$), and N2D+ (J=3−$2$) toward the millimeter multi-system MMS 2 in the Orion Molecular Cloud-3 region, at an angular resolution of 1.59" (∼620 au). MMS 2 is in the flat-spectrum phase, with its protostars in the late stage of the main accretion phase. We detect the centrally condensed structures traced by C18O emission associated with the 1.3 mm continuum sources MMS 2-North and MMS 2-South, which are spatially resolved and unresolved, respectively. The estimated diameter and mass of the centrally condensed structure associated with MMS 2-North are 1.64" (∼640 au) and 3.0×10−4M⊙, respectively. We also detect an extended structure traced by C18O emission associated the circumbinary envelope at scale of 5.70" (∼2240 au) with an estimated gas mass of 1.4×10−2M⊙. In addition, we detect a filamentary structure traced by N2D+ emission to the south of MMS 2, which is spatially offset from the C18O emission. This offset may be attributed to the influence of the warm surrounding environment.
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BibTeX
@misc{liu2026dense,
title = {{The Dense Gas Structures Around MMS 2/OMC-3 Traced by C$^18$O Emission}},
author = {Yuhua Liu and Satoko Takahashi and Masahiro N. Machida},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.09897},
eprint = {2609.09897},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.09897},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - The Dense Gas Structures Around MMS 2/OMC-3 Traced by C^18O Emission
AU - Yuhua Liu
AU - Satoko Takahashi
AU - Masahiro N. Machida
PY - 2026
DA - 2026/09/09
PB - arXiv
DO - 10.48550/arxiv.2609.09897
UR - https://arxiv.org/abs/2609.09897
AB - We report the Atacama Large Millimeter/submillimeter Array observations of 1.3 mm continuum, C^18O (J=2−$1$), and N_2D^+ (J=3−$2$) toward the millimeter multi-system MMS 2 in the Orion Molecular Cloud-3 region, at an angular resolution of 1.59" (∼620 au). MMS 2 is in the flat-spectrum phase, with its protostars in the late stage of the main accretion phase. We detect the centrally condensed structures traced by C^18O emission associated with the 1.3 mm continuum sources MMS 2-North and MMS 2-South, which are spatially resolved and unresolved, respectively. The estimated diameter and mass of the centrally condensed structure associated with MMS 2-North are 1.64" (∼640 au) and 3.0×10^−4M_⊙, respectively. We also detect an extended structure traced by C^18O emission associated the circumbinary envelope at scale of 5.70" (∼2240 au) with an estimated gas mass of 1.4×10^−2M_⊙. In addition, we detect a filamentary structure traced by N_2D^+ emission to the south of MMS 2, which is spatially offset from the C^18O emission. This offset may be attributed to the influence of the warm surrounding environment.
ER -