Stellar feedback on the earliest stage of massive star formation

• Verfasst von: Nayak, Omnarayani [VerfasserIn]
• Verfasst von: Chevance, Mélanie [VerfasserIn]
• Titel: Stellar feedback on the earliest stage of massive star formation
• Verf.angabe: O. Nayak, M. Meixner, Y. Okada, M.Y. Lee, M. Chevance, C. Buchbender, Y. Fukui, T. Onishi, A. Parikka, and J. Stutzki
• E-Jahr: 2021
• Jahr: 2021 February 3
• Umfang: 12 S.
• Fussnoten: Gesehen am 26.11.2021
• Titel Quelle: Enthalten in: The astrophysical journal / 1
• Ort Quelle: London : Institute of Physics Publ., 1996
• Jahr Quelle: 2021
• Band/Heft Quelle: 907(2021), 2, Artikel-ID 106, Seite 1-12
• ISSN Quelle: 1538-4357
• DOI: doi:10.3847/1538-4357/abcb89
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1751208184

Abstract

We report SOFIA/GREAT observations of high-J CO lines and [C ii] observations of the super star cluster candidate H72.97-69.39 in the Large Magellanic Cloud (LMC), which is in its very early formation stage. We use our observations to determine if shocks are heating the gas or if photon-dominated regions (PDRs) are being heated by local far-UV radiation. We use a PDR model and a shock model to determine whether the CO and [C ii] lines arise from PDRs or shocks. We can reproduce the observed high-J CO and [C ii] emission with a clumpy PDR model with the following properties: a density of 104.7 cm−3, a mass of 104 M⊙, and UV radiation of 103.5 in units of Draine field. Comparison with the ALMA beam-filling factor suggests a higher density within the uncertainty of the fit. We find the lower-limit [C ii]/total infrared (TIR) ratio (ϵ) traced by [C ii]/TIR to be 0.026%, lower than other known young star-forming regions in the LMC. Our shock models may explain the CO (16−15) and CO (11−10) emission lines with shock velocity of 8-11 km s−1, pre-shock density of 104-105 cm−3, and GUV = 0 in units of Draine field. However, the [C ii] line emission cannot be explained by a shock model, thus it is originating in a different gas component. Observations of [O i] 63 μm predicted to be 1.1 × 10−13 W m−2 by PDR models and 7.8 × 10−15 W m−2 by shock models will help distinguish between the PDR and shock scenarios.