Tracing the base of protostellar wind(s) towards the high-mass star forming region AFGL 5142: VLA continuum and VLBA water maser observations

Abstract

We have conducted phase-reference multi-epoch observations of the 22.2 GHz water masers using the VLBA and multi-frequency study of the continuum emission using the VLA towards the high-mass SFR AFGL 5142. The water maser emission comes from two elongated structures (indicated as Group I and Group II), with the measured proper motions aligned along the structures' elongation axes. Each group consists of two (blue- and red-shifted) clusters of features separated by a few hundreds and thousands of AU respectively for Group I and Group II. The maser features of Group II have both positions and velocities aligned along a direction close to the axis of the outflow traced by HCO+ and SiO emission on angular scales of tens of arcsec. We predict that the maser emission arises from dense, shocked molecular clumps displaced along the axis of the molecular outflow. The two maser clusters of Group I are oriented on the sky along a direction forming a large angle (> 60 degrees) with the axis of the jet/outflow traced by Group II maser features. We have detected a compact (8.4 and 22 GHz) continuum source that falls close to the centroid of Group I masers, indicating that the source ionizing the gas is also responsible for the excitation of the water masers. The kinematic analysis indicates that the Group I masers trace outflowing rather than rotating gas, discarding the Keplerian disk scenario proposed in a previous paper for Group I. Since the axis joining the two maser clusters of Group II does not cross the position of the continuum source, Group II masers might be excited by an (undetected) massive YSO, distinct from the one (pinpointed by the VLA continuum emission) responsible for the excitation of the Group I masers.

arXiv comment12 pages, 3 figures, accepted for publication in A&A

References in corpus (5)

• On the formation of massive stars
• Water masers in the massive protostar IRAS 20126+4104: ejection and deceleration
• Water Masers as Tracers of Protostellar Disks and Outflows in the Intermediate Mass Star Forming Region NGC 2071
• Kinematics of water masers in high-mass star forming regions
• EVN observations of water masers towards the high-mass young stellar object in AFGL 5142

Cited by in corpus (22)

• ALMA and ROSINA detections of phosphorus-bearing molecules: the interstellar thread between star-forming regions and comets
• Early stages of cluster formation: fragmentation of massive dense cores down to ~1000 AU
• Multiple Jets from the High-Mass (Proto)stellar Cluster AFGL5142
• Infall and outflow within 400 AU from a high-mass protostar. 3-D velocity fields from methanol and water masers in AFLG 5142
• N2H+ depletion in the massive protostellar cluster AFGL 5142
• A multiple system of high-mass YSOs surrounded by disks in NGC7538 IRS1
• Survey of Water and Ammonia in Nearby galaxies (SWAN): Resolved Ammonia Thermometry, Water and Methanol Masers in the Nuclear Starburst of NGC 253
• Intermediate-mass hot cores at 500 AU: disks or outflows?
• Associations of water and methanol masers at milli-arcsec angular resolution in two high-mass young stellar objects
• Protostellar Outflows at the EarliesT Stages (POETS). I. Radio thermal jets at high resolution nearby H${}_2$O maser sources
• A Galactic survey of radio jets from massive protostars
• Submillimeter Array Observations of 321 GHz Water Maser Emission in Cepheus A
• VLBA imaging of the 3mm SiO maser emission in the disk-wind from the massive protostellar system Orion Source I
• Protostellar Outflows at the EarliesT Stages (POETS). III. H2O masers tracing disk-winds and jets near luminous YSOs
• A collimated jet and an infalling-rotating disk in G192.16-3.84 traced by H2O maser emission
• H${}_2$O maser emission from bright rimmed clouds in the northern hemisphere
• 183 GHz H${}_2$O maser emission around the low-mass protostar Serpens SMM1
• Protostellar Outflows at the EarliesT Stages (POETS). IV. Statistical properties of the 22 GHz H2O masers
• Evidence of interacting elongated filaments in the star-forming site AFGL 5142
• Microstructure and kinematics of H2O masers in the massive star forming region IRAS 06061+2151
• Unbiased water and methanol maser surveys of NGC 1333
• Simultaneous 22 GHz Water and 44 GHz Methanol Masers Survey of Ultracompact HII Regions