High-Resolution Infrared Spectroscopy of IRS 16CC and IRS 33N: Stellar Parameters and Implications for Star Formation Near Sgr A*
Abstract
1. Introduction
2. Observations and Data Reduction
3. Modeling and Results
3.1. Synthetic Spectra
3.2. Photometry and Luminosity
3.3. BONNSAI
4. Discussion and Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
Abbreviations
| CW | Clockwise |
| F2 | Outer Filament 2 |
| GC | Galactic center |
| NIR | Near-infrared |
| NSC | Nuclear star cluster |
| Sgr A* | Sagittarius A star |
| SMBH | Supermassive black hole |
| WR | Wolf–Rayet |
| 1 | https://www.naoj.org/Observing/Instruments/IRCS/echelle/orders.html#K (accessed on 27 September 2025) |
| 2 | IRAF is distributed by the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA) under cooperative agreement with the National Science Foundation. |
| 3 | The spectral resolution of the observations presented in Tanner et al. [9] was sufficient to resolve the He I lines, and . Although their spectra are shown in the paper, there is no explicit statement that the two He I lines (21,126 and 21,138 Å) were used for determining stellar parameters. |
| 4 | https://www.astro.uni-bonn.de/stars/bonnsai/ (accessed on 27 September 2025) |
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| Object | ||||
|---|---|---|---|---|
| (K) | (dex) | (km s−1) | ||
| IRS 16CC | 24,000 ± 2000 | 2.25 ± 0.50 | 5.61 ± 0.12 | 70 ± 10 |
| IRS 33N | 24,000 ± 2000 | 2.25 ± 0.50 | 5.38 ± 0.12 |
| Object | SpT(a) | Age | |||||
|---|---|---|---|---|---|---|---|
| (K) | (dex) | () | (Myr) | (km s−1) | |||
| IRS 16CC | B0.5–1I | ||||||
| IRS 33N | B0.7–1.5I |
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Nishiyama, S.; Sato, W.; Hotta, M.; Ikarashi, M.; Saida, H.; Takamori, Y.; Nagata, T.; Ikeda, H.; Takahashi, M. High-Resolution Infrared Spectroscopy of IRS 16CC and IRS 33N: Stellar Parameters and Implications for Star Formation Near Sgr A*. Universe 2025, 11, 332. https://doi.org/10.3390/universe11100332
Nishiyama S, Sato W, Hotta M, Ikarashi M, Saida H, Takamori Y, Nagata T, Ikeda H, Takahashi M. High-Resolution Infrared Spectroscopy of IRS 16CC and IRS 33N: Stellar Parameters and Implications for Star Formation Near Sgr A*. Universe. 2025; 11(10):332. https://doi.org/10.3390/universe11100332
Chicago/Turabian StyleNishiyama, Shogo, Wakana Sato, Moeka Hotta, Momoka Ikarashi, Hiromi Saida, Yohsuke Takamori, Tetsuya Nagata, Hiroyuki Ikeda, and Masaaki Takahashi. 2025. "High-Resolution Infrared Spectroscopy of IRS 16CC and IRS 33N: Stellar Parameters and Implications for Star Formation Near Sgr A*" Universe 11, no. 10: 332. https://doi.org/10.3390/universe11100332
APA StyleNishiyama, S., Sato, W., Hotta, M., Ikarashi, M., Saida, H., Takamori, Y., Nagata, T., Ikeda, H., & Takahashi, M. (2025). High-Resolution Infrared Spectroscopy of IRS 16CC and IRS 33N: Stellar Parameters and Implications for Star Formation Near Sgr A*. Universe, 11(10), 332. https://doi.org/10.3390/universe11100332

