Dense Core Formation in Filamentary Clouds: Accretion toward Dense Cores from Filamentary Clouds and Gravitational Infall in the Cores

  • Kim, Shinyoung (Korea Astronomy and Space science Institute) ;
  • Lee, Chang Won (Korea Astronomy and Space science Institute) ;
  • Myers, Philip C. (Harvard-Smithsonian Center for Astrophysics) ;
  • Caselli, Paola (Max-Planck-Institut fur Extraterrestrische Physik (Center for Astrochemical Studies)) ;
  • Kim, Mi-Ryang (Korea Astronomy and Space science Institute) ;
  • Chung, Eun Jung (Korea Astronomy and Space science Institute)
  • Published : 2019.04.10

Abstract

Understanding how the filamentary structure affects the formation of the prestellar cores and stars is a key issue to challenge. We use the Heterodyne Array Receiver Program (HARP) of the James Clerk Maxwell Telescope (JCMT) to obtain molecular line mapping data for two prestellar cores in different environment, L1544 in filamentary cloud and L694-2 in a small cloud isolated. Observing lines are $^{13}CO$ and $C^{18}O$ (3-2) line to find possible flow motions along the filament, $^{12}CO$ (3-2) to search for any radial accretion (or infalling motions) toward the cores of gas material from their surrounding regions, and $HCO^+$ (4-3) lines to find at which density and which region in the core gases start to be in gravitational collapse. In the 1st moment maps of $^{13}CO$ and $C^{18}O$, velocity gradient patterns implying the flow of material were found at the cores and its surrounding filamentary clouds. The infall asymmetry patterns of HCO+ and $^{13}CO$ line profiles were detected to be good enough to analyze the infalling motions toward the cores. We will report further analysis results on core formation in the filamentary cloud at this meeting.

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