JWST View of the Supernebula in NGC 5253. II. Nebular Lines
6 affiliations
- 1Tel Aviv University
- 2UCLA
- 3Chalmers Institute of Technology
- 4Academia Sinica Astronomy and Astrophysics
- 5New Mexico Institute of Mining and Technology
- 6Instituto Nacional de Astrofísica Óptica y Electrónica
Abstract
The nearby dwarf starburst NGC 5253 is dominated by a compact radio-infrared supernebula powered by a very young and bright embedded super star cluster of ∼10 ⁹ L ⊙ . We observed this source and its surroundings over the 5–25 μ m range with the Mid-Infrared Instrument (MIRI) Medium Resolution Spectrometer (MRS) on JWST, and in Paper I presented the JWST view of the region and its continuum features. We now present the more than 70 emission lines of H I , H ₂ , and metal ions detected by MIRI/MRS. We derive the extinction by comparing H I recombination lines to the free–free radio continuum and find that it is very flat, i.e., almost independent of wavelength over this spectral range. Nebular conditions are consistent with young (≲5 × 10 ⁶ yr) and very massive stars. All regions show high excitation, but the spatial distribution of the high-excitation lines suggests that photons with energies close to 50 eV are escaping the supernebula core in spite of 35 mag of visual extinction.
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BibTeX
@article{beck2026jwst,
title = {{JWST View of the Supernebula in NGC 5253. II. Nebular Lines}},
author = {Sara C. Beck and Jean L. Turner and Elm Zweig and John H. Black and Paul T. P. Ho and David S. Meier and Sergiy Silich and Daniel P. Cohen and S. Michelle Consiglio and Nicholas G. Ferraro},
journal = {The Astrophysical Journal},
year = {2026},
month = nov,
doi = {10.3847/1538-4357/ae8519},
url = {https://iopscience.iop.org/article/10.3847/1538-4357/ae8519},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - JWST View of the Supernebula in NGC 5253. II. Nebular Lines
AU - Sara C. Beck
AU - Jean L. Turner
AU - Elm Zweig
AU - John H. Black
AU - Paul T. P. Ho
AU - David S. Meier
AU - Sergiy Silich
AU - Daniel P. Cohen
AU - S. Michelle Consiglio
AU - Nicholas G. Ferraro
PY - 2026
DA - 2026/11/04
JO - The Astrophysical Journal
DO - 10.3847/1538-4357/ae8519
UR - https://iopscience.iop.org/article/10.3847/1538-4357/ae8519
AB - The nearby dwarf starburst NGC 5253 is dominated by a compact radio-infrared supernebula powered by a very young and bright embedded super star cluster of ∼10 ⁹ L ⊙ . We observed this source and its surroundings over the 5–25 μ m range with the Mid-Infrared Instrument (MIRI) Medium Resolution Spectrometer (MRS) on JWST, and in Paper I presented the JWST view of the region and its continuum features. We now present the more than 70 emission lines of H I , H ₂ , and metal ions detected by MIRI/MRS. We derive the extinction by comparing H I recombination lines to the free–free radio continuum and find that it is very flat, i.e., almost independent of wavelength over this spectral range. Nebular conditions are consistent with young (≲5 × 10 ⁶ yr) and very massive stars. All regions show high excitation, but the spatial distribution of the high-excitation lines suggests that photons with energies close to 50 eV are escaping the supernebula core in spite of 35 mag of visual extinction.
SN - 1538-4357
SN - 0004-637X
ER -