{
  "id": "1711.08951",
  "version": "v1",
  "published": "2017-11-24T12:58:46.000Z",
  "updated": "2017-11-24T12:58:46.000Z",
  "title": "High-mass Star Formation through Filamentary Collapse and Clump-fed Accretion in G22",
  "authors": [
    "Jinghua Yuan",
    "Jin-Zeng Li",
    "Yuefang Wu",
    "Simon P. Ellingsen",
    "Christian Henkel",
    "Ke Wang",
    "Tie Liu",
    "Hong-Li Liu",
    "Annie Zavagno",
    "Zhiyuan Ren",
    "Ya-Fang Huang"
  ],
  "comment": "17 pages, 16 figures 3 tables. and Accepted for publication in ApJ",
  "categories": [
    "astro-ph.GA",
    "astro-ph.SR"
  ],
  "abstract": "How mass is accumulated from cloud-scale down to individual stars is a key open question in understanding high-mass star formation. Here, we present the mass accumulation process in a hub-filament cloud G22 which is composed of four supercritical filaments. Velocity gradients detected along three filaments indicate that they are collapsing with a total mass infall rate of about 440 $M_\\odot$ Myr$^{-1}$, suggesting the hub mass would be doubled in six free-fall times, adding up to $ \\sim2 $ Myr. A fraction of the masses in the central clumps C1 and C2 can be accounted for through large-scale filamentary collapse. Ubiquitous blue profiles in HCO$^+$ $ (3-2) $ and $^{13}$CO $ (3-2) $ spectra suggest a clump-scale collapse scenario in the most massive and densest clump C1. The estimated infall velocity and mass infall rate are 0.31 km s$^{-1}$ and $ 7.2 \\times10^{-4} $ $M_\\odot$ yr$^{-1}$, respectively. In clump C1, a hot molecular core (SMA1) is revealed by the SMA observations and an outflow-driving high-mass protostar is located at the center of SMA1. The mass of the protostar is estimated to be $ 11-15 $ $M_\\odot$ and it is still growing with an accretion rate of $ 7\\times10^{-5} $ $M_\\odot$ yr$^{-1}$. The coexistent infall in filaments, clump C1, and the central hot core in G22 suggests that pre-assembled mass reservoirs (i.e., high-mass starless cores) may not be required to form high-mass stars. In the course of high-mass star formation, the central protostar, the core, and the clump can simultaneously grow in mass via core-fed/disk accretion, clump-fed accretion, and filamentary/cloud collapse.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2017-11-24T12:58:46.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "high-mass star formation",
      "filamentary collapse",
      "clump-fed accretion",
      "clump c1",
      "total mass infall rate"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 17,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}