ALMA discovery of a dual dense probably rotating outflow from a massive young stellar object G18.88MME

I. I. Zinchenko; L. K. Dewangan; T. Baug; D. K. Ojha; N. K. Bhadari

doi:10.1093/mnrasl/slab070

paper

ALMA discovery of a dual dense probably rotating outflow from a massive young stellar object G18.88MME

arXiv:2106.09626 · doi:10.1093/mnrasl/slab070

Abstract

We report the discovery of a very dense jet-like fast molecular outflow surrounded by a wide-angle wind in a massive young stellar object (MYSO) G18.88MME (stellar mass $\sim$ 8 M $_{⊙}$ ) powering an Extended Green Object G18.89 $-$ 0.47. Four cores MM1-4 are identified in the Atacama Large Millimeter/submillimeter Array (ALMA) 1.3 mm continuum map (resolution $\sim$ 0. $"$ 8) toward G18.88MME, and are seen at the center of the emission structure (extent $\sim$ 0.3 pc $\times$ 0.2 pc) detected in the ALMA map. G18.88MME is embedded in the core MM1 (mass $\sim$ 13-18 M $_{⊙}$ ), where no radio continuum emission is detected. The molecular outflow centered at MM1 is investigated in the SiO(5-4), HC $_{3}$ N(24-23) and $^{13}$ CO(2-1) lines. The detection of HC $_{3}$ N in the outflow is rare in MYSOs and indicates its very high density. The position-velocity diagrams display a fast narrow outflow (extent $\sim$ 28000 AU) and a slower wide-angle more extended outflow toward MM1, and both of these components show a transverse velocity gradient indicative of a possible rotation. All these observed features together make G18.88MME as a unique object for studying the unification of the jet-driven and wind-driven scenarios of molecular outflows in MYSOs.

5 pages, 6 figures, accepted for publication in Monthly Notices of the Royal Astronomical Society

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Cited by in corpus (1)

The ALMA-ATOMS survey: Vibrationally excited HC $_{3}$ N lines in hot cores