Article Dans Une Revue The Astrophysical Journal Année : 2025

Unveiling two deeply embedded young protostars in the S68N Class 0 protostellar core with JWST/NIRSpec

Valentin Gouellec
  • Fonction : Auteur
Ben Lew
  • Fonction : Auteur
Thomas Greene
  • Fonction : Auteur
Antoine Gusdorf
Curtis Dewitt
  • Fonction : Auteur
Michael Meyer
  • Fonction : Auteur
Mary Barsony
  • Fonction : Auteur
Klaus Hodapp
  • Fonction : Auteur

Résumé

The near-infrared (NIR) emission of the youngest protostars still needs to be characterized to better understand the evolution of their accretion and ejection activity. We analyze James Webb Space Telescope NIRSpec 1.7 -- 5.3 $μ$m observations of two deeply embedded sources in the S68N protostellar core in Serpens. The North Central (NC) source exhibits a highly obscured spectrum (A_K ~ 4.8 mag) that is modeled with a pre-main-sequence photosphere and a hot disk component. The photospheric parameters are consistent with a young, low-mass photosphere, as suggested by the low surface gravity, log g of 1.94 $\pm$ 0.15 cm s$^{-2}$. The hot disk suggests that accretion onto the central protostellar embryo is ongoing, although prototypical accretion-tracing emission lines HI are not detected. The South Central (SC) source, which is even more embedded (A_K ~ 8 mag; no continuum is detected shortward of 3.6 $μ$m) appears to be driving the large-scale S68N protostellar outflow, and launches a collimated hot molecular jet detected in \Ht and CO ro-vibrational lines. Shock modeling of the \Ht (ro)vibrational lines establishes that fast $C$-type shocks ($\geq$ 30 km s$^{-1}$), with high pre-shock density ($\geq$ $10^7$ cm$^{-3}$), and strong magnetic field (b ~ 3--10, where $B = b\,\times\,\sqrt{\textrm{n}_{\textrm{H}} (\textrm{cm}^{-3})}\,μ\textrm{G}$) best match the data. The bright CO fundamental line forest suggests energetic excitation, with the contribution of non-LTE effects, ie irradiation pumping. Detected OH and CH$^{+}$ ro-vibrational lines support this hypothesis. These two Class 0 protostars seem to be in very young evolutionary stages and still have to acquire the bulk of their final stellar masses. These results demonstrate that JWST enables unprecedented diagnostics of these first stages of the protostellar evolutionary phase.

Fichier principal
Vignette du fichier
Le_Gouellec_2025_ApJ_985_225.pdf (19.95 Mo) Télécharger le fichier
Origine Fichiers éditeurs autorisés sur une archive ouverte
Licence
DOI

Cite 10.17909/phr8-cz37 Jeu de données Le Gouellec, Valentin. (2024). Data from Le Gouellec et al. 2024b [Data set]. STScI/MAST. https://doi.org/10.17909/PHR8-CZ37

Dates et versions

hal-04779834 , version 1 (27-08-2025)

Licence

Identifiants

Citer

Valentin Gouellec, Ben Lew, Thomas Greene, Doug Johnstone, Antoine Gusdorf, et al.. Unveiling two deeply embedded young protostars in the S68N Class 0 protostellar core with JWST/NIRSpec. The Astrophysical Journal, 2025, 985 (2), pp.225. ⟨10.3847/1538-4357/adcac4⟩. ⟨hal-04779834⟩
192 Consultations
56 Téléchargements

Altmetric

Partager

  • More