Detection of Aliphatically Deuterated Aromatic Hydrocarbons in the Large Magellanic Cloud 30 Doradus Star-forming Complex
- 1Xiangtan University
- 2University of Missouri
Abstract
The “unidentified infrared (IR) emission” (UIE) bands at 3.3, 6.2, 7.7, 8.6, 11.3, and 12.7 μ m are ubiquitously seen in a wide variety of astrophysical environments. While the exact assignment of these UIE bands remains controversial, they are generally ascribed to C–H and C–C stretching and bending vibrations of aromatic hydrocarbon molecules. Here, based on observations made with the Near-Infrared Spectrograph (NIRSpec) and the Mid-Infrared Instrument (MIRI) on board the James Webb Space Telescope (JWST), we report that the UIE emitters in the 30 Doradus star-forming complex in the Large Magellanic Cloud (LMC) are deuterated and have an appreciable amount of aliphatic content. The spatially resolved NIRSpec and MIRI spectra of 30 Doradus reveal a widespread detection of the 3.4 and 6.85 μ m emission features attributed to aliphatic C–H stretch and deformation, respectively, as well as the 4.65 μ m feature attributed to aliphatic C–D stretch. Notably, the 6.85 μ m feature exhibits three complex substructures at ∼6.83, 6.86, and 6.88 μ m that have never been reported before.
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BibTeX
@article{peng2026detection,
title = {{Detection of Aliphatically Deuterated Aromatic Hydrocarbons in the Large Magellanic Cloud 30 Doradus Star-forming Complex}},
author = {Junhao Peng and Xuejuan Yang and Aigen Li},
journal = {The Astrophysical Journal},
year = {2026},
month = oct,
doi = {10.3847/1538-4357/ae9a80},
url = {https://iopscience.iop.org/article/10.3847/1538-4357/ae9a80},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Detection of Aliphatically Deuterated Aromatic Hydrocarbons in the Large Magellanic Cloud 30 Doradus Star-forming Complex
AU - Junhao Peng
AU - Xuejuan Yang
AU - Aigen Li
PY - 2026
DA - 2026/10/07
JO - The Astrophysical Journal
DO - 10.3847/1538-4357/ae9a80
UR - https://iopscience.iop.org/article/10.3847/1538-4357/ae9a80
AB - The “unidentified infrared (IR) emission” (UIE) bands at 3.3, 6.2, 7.7, 8.6, 11.3, and 12.7 μ m are ubiquitously seen in a wide variety of astrophysical environments. While the exact assignment of these UIE bands remains controversial, they are generally ascribed to C–H and C–C stretching and bending vibrations of aromatic hydrocarbon molecules. Here, based on observations made with the Near-Infrared Spectrograph (NIRSpec) and the Mid-Infrared Instrument (MIRI) on board the James Webb Space Telescope (JWST), we report that the UIE emitters in the 30 Doradus star-forming complex in the Large Magellanic Cloud (LMC) are deuterated and have an appreciable amount of aliphatic content. The spatially resolved NIRSpec and MIRI spectra of 30 Doradus reveal a widespread detection of the 3.4 and 6.85 μ m emission features attributed to aliphatic C–H stretch and deformation, respectively, as well as the 4.65 μ m feature attributed to aliphatic C–D stretch. Notably, the 6.85 μ m feature exhibits three complex substructures at ∼6.83, 6.86, and 6.88 μ m that have never been reported before.
SN - 0004-637X
SN - 1538-4357
ER -