Inflow Motions Associated with High-mass Protostellar Objects

Hyunju Yoo, Kee Tae Kim, Jungyeon Cho, Minho Choi, Jingwen Wu, Neal J. Evans, Lucy M Ziurys

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

We performed a molecular line survey of 82 high-mass protostellar objects in a search for inflow signatures associated with high-mass star formation. Using the H13CO+ (1-0) line as an optically thin tracer, we detected a statistically significant excess of blue asymmetric line profiles in the HCO+ (1-0) transition, but nonsignificant excesses in the HCO+ (3-2) and H2CO (212-111) transitions. The negative blue excess for the HCN (3-2) transition suggests that the line profiles are affected by dynamics other than inflow motion. The HCO+ (1-0) transition thus seems to be the suitable tracer of inflow motions in high-mass star-forming regions, as previously suggested. We found 27 inflow candidates that have at least 1 blue asymmetric profile and no red asymmetric profile, and derived the inflow velocities to be 0.23-2.00 km s-1 for 20 of them using a simple two-layer radiative transfer model. Our sample is divided into two groups in different evolutionary stages. The blue excess of the group in relatively earlier evolutionary stages was estimated to be slightly higher than that of the other in the HCO+ (1-0) transition.

Original languageEnglish (US)
Article number31
JournalAstrophysical Journal, Supplement Series
Volume235
Issue number2
DOIs
StatePublished - Apr 1 2018

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inflow
profiles
tracers
tracer
radiative transfer
star formation
signatures
stars

Keywords

  • ISM: kinematics and dynamics
  • ISM: molecules
  • radio lines: ISM
  • stars: formation

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Inflow Motions Associated with High-mass Protostellar Objects. / Yoo, Hyunju; Kim, Kee Tae; Cho, Jungyeon; Choi, Minho; Wu, Jingwen; Evans, Neal J.; Ziurys, Lucy M.

In: Astrophysical Journal, Supplement Series, Vol. 235, No. 2, 31, 01.04.2018.

Research output: Contribution to journalArticle

Yoo, Hyunju ; Kim, Kee Tae ; Cho, Jungyeon ; Choi, Minho ; Wu, Jingwen ; Evans, Neal J. ; Ziurys, Lucy M. / Inflow Motions Associated with High-mass Protostellar Objects. In: Astrophysical Journal, Supplement Series. 2018 ; Vol. 235, No. 2.
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