A Systematic Search for Molecular Outflows Toward Candidate Low-Luminosity Protostars and Very Low Luminosity Objects

Abstract

We present a systematic single-dish search for molecular outflows toward a sample of 9 candidate low-luminosity protostars and 30 candidate Very Low Luminosity Objects (VeLLOs; L_int < 0.1 L_sun). The sources are identified using data from the Spitzer Space Telescope catalogued by Dunham et al. toward nearby (D < 400 pc) star forming regions. Each object was observed in 12CO and 13CO J = 2-1 simultaneously using the sideband separating ALMA Band-6 prototype receiver on the Heinrich Hertz Telescope at 30 arcsecond resolution. Using 5-point grid maps we identify five new potential outflow candidates and make on-the-fly maps of the regions surrounding sources in the dense cores B59, L1148, L1228, and L1165. Of these new outflow candidates, only the map of B59 shows a candidate blue outflow lobe associated with a source in our survey. We also present larger and more sensitive maps of the previously detected L673-7 and the L1251-A IRS4 outflows and analyze their properties in comparison to other outflows from VeLLOs. The accretion luminosities derived from the outflow properties of the VeLLOs with detected CO outflows are higher than the observed internal luminosity of the protostars, indicating that these sources likely had higher accretion rates in the past. The known L1251-A IRS3 outflow is detected but not remapped. We do not detect clear, unconfused signatures of red and blue molecular wings toward the other 31 sources in the survey indicating that large-scale, distinct outflows are rare toward this sample of candidate protostars. Several potential outflows are confused with kinematic structure in the surrounding core and cloud. Interferometric imaging is needed to disentangle large-scale molecular cloud kinematics from these potentially weak protostellar outflows.

42 pages, 19 figures, Accepted for publication in the Astronomical Journal

References in corpus (12)

• The Evolution of Outflow-Envelope Interactions in Low-Mass Protostars
• Identifying the Low Luminosity Population of Embedded Protostars in the c2d Observations of Clouds and Cores
• Resolving the Luminosity Problem in Low-Mass Star Formation
• The On The Fly Imaging Technique
• The Spitzer c2d Survey of Nearby Dense Cores: I: First Direct Detection of the Embedded Source in IRAM 04191+1522
• The enigmatic core L1451-mm: a first hydrostatic core? or a hidden VeLLO?
• Detection of a Bipolar Molecular Outflow Driven by a Candidate First Hydrostatic Core
• Nonlinear Evolution of Global Hydrodynamic Shallow-Water Instability in Solar Tachocline
• The Spitzer c2d Survey of Nearby Dense Cores: IV. Revealing the Embedded Cluster in B59
• SMA and Spitzer Observations of Bok Glouble CB17: A Candidate First Hydrostatic Core?
• The Detection and Characterization of cm Radio Continuum Emission from the Low-mass Protostar L1014-IRS
• A CO (J=3-2) Outflow Survey of the Elias 29 Region

Cited by in corpus (10)

• IC348-SMM2E: a Class 0 proto-brown dwarf candidate forming as a scaled-down version of low-mass stars
• Direct Imaging of a Compact Molecular Outflow from a Very Low-luminosity Object; L1521F-IRS
• Magnetic field structure around cores with very low luminosity objects
• The Evolution of Protostellar Outflow Cavities, Kinematics, and Angular Distribution of Momentum and Energy in Orion A: Evidence for Dynamical Cores
• Widening of Protostellar Outflows: an Infrared Outflow Survey in Low Luminosity Objects
• Probing the magnetic fields in L1415 and L1389
• CO Outflow Survey of 68 Very Low Luminosity Objects: a Search for Proto-Brown Dwarf Candidates
• The nature of very low luminosity objects (VeLLOs)
• A search for cloud cores affected by shocked carbon chain chemistry in L1251
• A search for water maser emission from brown dwarfs and low-luminosity young stellar objects