X-Shooting ULLYSES: Massive Stars at Low Metallicity X. Physical Parameters and Feedback of Massive Stars in the LMC N11 B Star-Forming Region

Gómez-González, V.M.A.; Oskinova, L.M.; Hamann, W. R.; Todt, H.; Pauli, D.; Reyero Serantes, S.; Bernini-Peron, M.; Sander, A.C.; Ramachandran, V.; Vink, J.S.; Crowther, P.A.; Berlanas, S.R.; ud-Doula, A.; Gormaz-Matamala, A.C.; Kehrig, C.; Kuiper, R.; Leitherer, C.; Mahy, L.; McLeod, A.F.; Mehner, A.; Morrell, N.; Shenar, T.; Telford, O.G.; Th. van Loon, J.; Tramper, F.; Wofford, A.

Abstract

Massive stars drive the ionization and mechanical feedback within young star-forming regions. The Large Magellanic Cloud (LMC) is an ideal galaxy for studying individual massive stars and quantifying their feedback contribution to the environment. We analyze eight exemplary targets in LMC N11 B from the Hubble UV Legacy Library of Young Stars as Essential Standards (ULLYSES) program using novel spectra from HST (COS and STIS) in the UV, and from VLT (X-shooter) in the optical. We model the spectra of early to late O-type stars using state-of-the-art PoWR atmosphere models. We determine the stellar and wind parameters (e.g., T⋆, log g, L⋆, Ṁ, and v∞) of the analyzed objects, chemical abundances (C, N, and O), ionizing and mechanical feedback (QH, QHeI, QHe II, and Lmec), and X-rays. We report ages of 2–4.5 Myr and masses of 30–60 M⊙ for the analyzed stars in N11 B, which are consistent with a scenario of sequential star formation. We note that the observed wind-momentum–luminosity relation is consistent with theoretical predictions. We detect nitrogen enrichment by up to a factor of seven in most of the stars. However, we do not find a correlation between nitrogen enrichment and projected rotational velocity. Finally, based on their spectral type, we estimate the total ionizing photons injected from the O-type stars in N11 B into its environment. We report log (Σ QH) = 50.5 ph s−1, log (Σ QHe I) = 49.6 ph s−1, and log (Σ QHe II)= 44.4 ph s−1, consistent with the total ionizing budget in N11.

Citation

Gómez-González, V., Oskinova, L., Hamann, W. R., Todt, H., Pauli, D., Reyero Serantes, S., Bernini-Peron, M., Sander, A., Ramachandran, V., Vink, J., Crowther, P., Berlanas, S., ud-Doula, A., Gormaz-Matamala, A., Kehrig, C., Kuiper, R., Leitherer, C., Mahy, L., McLeod, A., Mehner, A., …Wofford, A. (2025). X-Shooting ULLYSES: Massive Stars at Low Metallicity X. Physical Parameters and Feedback of Massive Stars in the LMC N11 B Star-Forming Region. Astronomy and Astrophysics, 695, 18. https://doi.org/10.1051/0004-6361/202451366

• Journal Article Type: Article
• Acceptance Date: Nov 21, 2024
• Online Publication Date: Mar 20, 2025
• Publication Date: 2025-03
• Journal: Astronomy and Astrophysics
• Print ISSN: 2329-1273
• Electronic ISSN: 2329-1265
• Publisher: Hans Publishers
• Peer Reviewed: Peer Reviewed
• Volume: 695
• Article Number: A197
• Pages: 18
• DOI: https://doi.org/10.1051/0004-6361/202451366
• Keywords: stars: atmospheres / stars: fundamental parameters / stars: massive / stars: mass-loss / stars: winds, outflows / HII regions
• Public URL: https://keele-repository.worktribe.com/output/1014855