ATOMS: ALMA three-millimeter observations of massive star-forming regions -XIII. Ongoing triggered star formation within clump-fed scenario found in the massive ( 1500 M⊙) clump

Autor: Siju Zhang, Ke Wang, Tie Liu, Annie Zavagno, Mika Juvela, Hongli Liu, Anandmayee Tej, Amelia M Stutz, Shanghuo Li, Leonardo Bronfman, Qizhou Zhang, Paul F Goldsmith, Chang Won Lee, Enrique Vázquez-Semadeni, Ken’ichi Tatematsu, Wenyu Jiao, Fengwei Xu, Chao Wang, Jian-Wen Zhou
Přispěvatelé: Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: Monthly Notices of the Royal Astronomical Society
Monthly Notices of the Royal Astronomical Society, 2023, ⟨10.1093/mnras/stad011⟩
ISSN: 0035-8711
1365-2966
DOI: 10.1093/mnras/stad011⟩
Popis: Whether ionization feedback triggers the formation of massive stars is highly debated. Using ALMA 3 mm observations with a spatial resolution of $\sim 0.05$ pc and a mass sensitivity of 1.1 $\rm M_\odot$ beam$^{-1}$ at 20 K, we investigate the star formation and gas flow structures within the ionizing feedback-driven structure, a clump-scale massive ($\gtrsim 1500$ $\rm M_\odot$) bright-rimmed cloud (BRC) associated with IRAS 18290-0924. This BRC is bound only if external compression from ionized gas is considered. A small-scale ($\lesssim1$ pc) age sequence along the direction of ionizing radiation is revealed for the embedded cores and protostars, which suggests triggered star formation via radiation-driven implosion (RDI). Furthermore, filamentary gas structures converge towards the cores located in the BRC's center, indicating that these filaments are fueling mass towards cores. The local core-scale mass infall rate derived from H$^{13}$CO$^+$ $J=1-0$ blue profile is of the same order of magnitude as the filamentary mass inflow rate, approximately 1 $\rm M_\odot$ kyr$^{-1}$. A photodissociation region (PDR) covering the irradiated clump surface is detected in several molecules, such as CCH, HCO$^+$, and CS whereas the spatial distribution stratification of these molecules is indistinct. CCH spectra of the PDR possibly indicate a photoevaporation flow leaving the clump surface with a projected velocity of $\sim2$ km s$^{-1}$. Our new observations show that RDI accompanied by a clump-fed process is operating in this massive BRC. Whether this combined process works in other massive BRCs is worth exploring with dedicated surveys.
34 pages with 20 figures, Accepted by MNRAS on 2022 December 28
Databáze: OpenAIRE