An APEX survey of outflow and infall toward the youngest protostars in Orion

Abstract

We aim to characterize the outflow properties of a sample of early Class 0 phase low-mass protostars in Orion first identified by the Herschel Space Observatory. We also look for signatures of infall in key molecular lines. CO $J$=3-2 and $J$=4-3 maps toward 16 very young Class 0 protostars were obtained using the Atacama Pathfinder EXperiment (APEX) telescope. We search the data for line wings indicative of outflows and calculate masses, velocities, and dynamical times for the outflows. We use additional HCO${}^{+}$, H${}^{13}$CO${}^{+}$, and NH${}_3$ lines to look for infall signatures toward the protostars. We estimate the outflow masses, forces, and mass-loss rates based on the CO $J$=3-2 and $J$=4-3 line intensities for 8 sources with detected outflows. We derive upper limits for the outflow masses and forces of sources without clear outflow detections. The total outflow masses for the sources with clear outflow detections are in the range between 0.03 and 0.16 $M_{\odot }$ for CO $J$=3-2, and in the range between 0.02 and 0.10 $M_{\odot }$ for CO $J$=4-3. The outflow forces are in the range between $1.57\times 10^{-4}$ and $1.16\times 10^{-3}$ $M_{\odot }$ km s${}^{-1}$ yr${}^{-1}$ for CO $J$=3-2 and in the range between $1.14\times 10^{-4}$ and $6.92\times 10^{-4}$ $M_{\odot }$ km s${}^{-1}$ yr${}^{-1}$ for CO $J$=4-3. Nine protostars in our sample show asymmetric line profiles indicative of infall in HCO${}^{+}$, compared to H${}^{13}$CO${}^{+}$ or NH${}_3$. The outflow forces of the protostars in our sample show no correlation with the bolometric luminosity, unlike those found by some earlier studies for other Class 0 protostars. The derived outflow forces for the sources with detected outflows are similar to those found for other - more evolved - Class 0 protostars, suggesting that outflows develop quickly in the Class 0 phase.

arXiv commentAccepted for publication in A&A

References in corpus (24)

• Theory of Star Formation
• The Spitzer c2d Legacy Results: Star Formation Rates and Efficiencies; Evolution and Lifetimes
• The distance to the Orion Nebula
• The Spitzer Space Telescope Survey of the Orion A & B Molecular Clouds - Part I: A Census of Dusty Young Stellar Objects and a Study of their Mid-IR Variability
• 2-D Radiative Transfer in Protostellar Envelopes: II. An Evolutionary Sequence
• A Search for Infall Motions Toward Nearby Young Stellar Objects
• The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Orion Protostars. A Statistical Characterization of Class 0 and I Protostellar Disks
• The Evolution of Outflow-Envelope Interactions in Low-Mass Protostars
• The Herschel Orion Protostar Survey: Spectral Energy Distributions and Fits Using a Grid of Protostellar Models
• A Herschel and APEX Census of the Reddest Sources in Orion: Searching for the Youngest Protostars
• The Spitzer Space Telescope Survey of the Orion A and B Molecular Clouds II: the Spatial Distribution and Demographics of Dusty Young Stellar Objects
• Evolution of Protostellar Outflow around Low-mass Protostar
• Molecular Outflows Driven by Low-Mass Protostars. I. Correcting for Underestimates When Measuring Outflow Masses and Dynamical Properties
• A submillimetre survey of the kinematics of the Perseus molecular cloud - II. Molecular outflows
• The Luminosities of Protostars in the Spitzer c2d and Gould Belt Legacy Clouds
• APEX-CHAMP+ high-J CO observations of low-mass young stellar objects: IV. Mechanical and radiative feedback
• Herschel/PACS Spectroscopic Survey of Protostars in Orion: The Origin of Far-Infrared CO Emission
• Millimeter- and Submillimeter-Wave Observations of the OMC-2/3 Region. III. An Extensive Survey for Molecular Outflows
• Outflow forces of low mass embedded objects in Ophiuchus: a quantitative comparison of analysis methods
• JCMT HARP CO 3-2 Observations of Molecular Outflows in W5
• Characterizing the Youngest Herschel-detected Protostars I. Envelope Structure Revealed by CARMA Dust Continuum Observations
• Characterizing the Youngest Herschel-detected Protostars II. Molecular Outflows from the Millimeter and the Far-infrared
• Detection of Irregular, Sub-mm Opaque Structures in the Orion Molecular Clouds: Protostars within 10000 years of formation?
• Outflow forces in intermediate mass star formation

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