IRAS16547-4247: A New Candidate of a Protocluster Unveiled with ALMA

Abstract

We present the results of continuum and 12CO(3-2) and CH3OH(7-6) line observations of IRAS16547-4247 made with the Atacama Large Millimeter/submillimeter Array (ALMA) at an angular resolution of ~0.5". The 12CO(3-2) emission shows two high-velocity outflows whose driving sources are located within the dust continuum peak. The alignment of these outflows do not coincide with that of the wide-angle, large scale, bipolar outflow detected with APEX in previous studies. The CH3OH(7-6) line emission traces an hourglass structure associated with the cavity walls created by the outflow lobes. Taking into account our results together with the position of the H2O and class I CH3OH maser clusters, we discuss two possible scenarios that can explain the hourglass structure observed in IRAS16547-4247: (1) precession of a biconical jet, (2) multiple, or at least two, driving sources powering intersecting outflows. Combining the available evidence, namely, the presence of two cross-aligned bipolar outflows and two different H2O maser groups, we suggest that IRAS16547-4247 represents an early formation phase of a protocluster.

arXiv commentAccepted by ApJL

References in corpus (20)

• Embedded Clusters in Molecular Clouds
• Theory of Star Formation
• Toward Understanding Massive Star Formation
• Non-thermal desorption from interstellar dust grains via exothermic surface reactions
• Class I methanol masers in the outflow of IRAS 16547-4247
• A necklace of dense cores in the high-mass star forming region G35.20-0.74N: ALMA observations
• Distinct Chemical Regions in the "Prestellar" Infrared Dark Cloud (IRDC) G028.23-00.19
• A 13CO and C18O Survey of the Molecular Gas Around Young Stellar Clusters Within 1kpc of the Sun
• A wide-angle outflow with the simultaneous presence of a high-velocity jet in the high-mass Cepheus A HW2 system
• The physics and modes of star cluster formation: observations
• High Angular Resolution Observations of the Collimated Jet Source Associated with a Massive Protostar in IRAS 16547-4247
• The Collimated Jet Source in IRAS 16547-4247: Time Variation, Possible Precession, and Upper Limits to the Proper Motions Along the Jet Axis
• A Mapping Survey of Dense Clumps Associated with Embedded Clusters : Evolutionary Stages of Cluster-Forming Clumps
• ALMA Observations of the IRDC Clump G34.43+00.24 MM3: Hot Core and Molecular Outflows
• Slow ionized wind and rotating disklike system associated with the high-mass young stellar object G345.4938+01.4677
• ALMA view of G0.253+0.016: Can cloud-cloud collision form the cloud?
• A Mapping Survey of Dense Clumps Associated with Embedded Clusters II : Can Clump-Clump Collisions Induce Stellar Clusters?
• The Rotating Molecular Structures and the Ionized Outflow Associated with IRAS 16547-4247
• ALMA Observations of the IRDC Clump G34.43+00.24 MM3: 278 GHz Class I Methanol Masers
• Maps of Massive Clumps in the Early Stage of Cluster Formation: Two Modes of Cluster Formation, Coeval or Non-Coeval?

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• Tracing Embedded Stellar Populations in Clusters and Galaxies using Molecular Emission: Methanol as a Signature of the Low-Mass End of the IMF
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