A Survey for Infall Motions toward Starless Cores. I. CS (2-1) and N${}_2$H${}^{+}$ (1-0) Observations

Abstract

In this paper, we present the first results of a survey of 220 starless cores selected primarily by their optical obscuration (Lee & Myers 1999) and observed in CS (2-1), N${}_2$H${}^{+}$ (1-0), and C${}^{18}$O (1-0) using the NEROC Haystack 37-m telescope, to quantify the incidence of infall motions toward starless cores and find infall candidates for further study in the future.

26 pages, 9 figures (13 PS files), accepted for publication to ApJ

References in corpus (4)

• A Search for Infall Motions Toward Nearby Young Stellar Objects
• A Catalogue of Optically Selected Cores
• A High Resolution Study of the Slowly Contracting, Starless Core L1544
• Turbulent Cooling Flows in Molecular Clouds

Cited by in corpus (137)

• Theory of Star Formation
• Control of star formation by supersonic turbulence
• Cold Dark Clouds: The Initial Conditions for Star Formation
• Dense Cores in Dark Clouds. XIV. N2H+(1-0) maps of dense cloud cores
• Systematic Molecular Differentiation in Starless Cores
• Probing the evolutionary status of starless cores through N2H+ and N2D+ observations
• Efficiencies of Low-Mass Star and Star Cluster Formation
• Tracing the Mass during Low-Mass Star Formation. I. Submillimeter Continuum Observations
• A Survey for Infall Motions toward Starless Cores. II. $CS(2-1)$ and $N_2{H}^{+}(1-0)$ Mapping Observations
• A Catalogue of Optically Selected Cores
• Dense core formation by fragmentation of velocity-coherent filaments in L1517
• An Infrared/X-ray Survey for New Members of the Taurus Star-Forming Region
• An empirical model for protostellar collapse
• The Circumstellar Environment of High Mass Protostellar Objects. III Evidence of Infall?
• Chains of dense cores in the Taurus L1495/B213 complex
• Near Infrared Imaging Survey of Bok Globules: Density Structure
• Multilayer formation and evaporation of deuterated ices in prestellar and protostellar cores
• Molecular Outflows Driven by Low-Mass Protostars. I. Correcting for Underestimates When Measuring Outflow Masses and Dynamical Properties
• On the frequency of N2H+ and N2D+
• The Different Structures of the Two Classes of Starless Cores
• Quiescent Cores and the Efficiency of Turbulence-Accelerated, Magnetically Regulated Star Formation
• Chemistry and Dynamics in Pre-Protostellar Cores
• Observations of L1521F: a highly evolved starless core
• Indications of Inflow Motions in Regions Forming Massive Stars
• The Excitation of N${}_2$H${}^{+}$ in Interstellar Molecular Clouds. I - Models
• A Survey For Infall Motions Toward Starless Cores. III. CS (3-2) and DCO+(2-1) Observations
• Molecular Line Profile Fitting with Analytic Radiative Transfer Models
• Magnetically Regulated Star Formation in Turbulent Clouds
• Protostellar Collapse Induced by Compression
• ATOMS: ALMA Three-millimeter Observations of Massive Star-forming regions -- XV. Steady Accretion from Global Collapse to Core Feeding in Massive Hub-filament System SDC335
• Line Profiles of Cores within Clusters: I. The Anatomy of a Filament
• How to Identify Pre-Protostellar Cores
• Droplets I: Pressure-Dominated Sub-0.1 pc Coherent Structures in L1688 and B18
• Signatures of inflow motion in cores of massive star formation: Potential collapse candidates
• Generalized Collapse Solutions with Nonzero Initial Velocities for Star Formation in Molecular Cloud Cores
• L1521E: A Starless Core in the Early Evolutionary Stage ?
• Probing Inward Motions in Starless Cores Using The HCN J = 1-0 Hyperfine Transitions : A Pointing Survey Toward Central Regions
• A Search for Infall Evidence in EGOs I: the Northern Sample
• Dark cloud cores and gravitational decoupling from turbulent flows
• Searching for chameleon-like scalar fields with the ammonia method
• Protostar Formation in Supersonic Flows: Growth and Collapse of Spherical Cores
• Deep Near-Infrared Observations of L1014: Revealing the nature of the core and its embedded source
• The Spitzer c2d Survey of Nearby Dense Cores. V. Discovery of a VeLLO in the "Starless" Dense Core L328
• Centrally Condensed Collapse of Starless Cores
• A MALT90 study of the chemical properties of massive clumps and filaments of infrared dark clouds
• Protostellar collapse induced by compression. II: rotation and fragmentation
• The Spitzer c2d Survey of Nearby Dense Cores. IX. Discovery of a Very Low Luminosity Object Driving a Molecular Outflow in the Dense Core L673-7
• Oscillations of starless cores
• The nature of the dense core population in the pipe nebula: core and cloud kinematics from C18O observations
• JCMT POL-2 and BISTRO Survey observations of magnetic fields in the L1689 molecular cloud
• Dynamical and chemical properties of the "starless" core L1014
• Spitzer and HHT observations of starless cores: masses and environments
• Laboratory and space spectroscopy of DCO+
• Molecular gas freeze-out in the pre-stellar core L1689B
• Observation of HCN hyperfine line anomalies towards low- and high-mass star-forming cores
• Formation and Collapse of Quiescent Cloud Cores Induced by Dynamic Compressions
• Constraints on star formation theories from the Serpens molecular cloud and protocluster
• Protostar Mass Due to Infall and Dispersal
• A quantification of the non-spherical geometry and accretion of collapsing cores
• N2H+ Observations of Molecular Cloud Cores in Taurus
• Chemical differentiation in regions of high-mass star formation I. CS, dust and N2H^+ in southern sources
• The Five Planets in the Kepler-296 Binary System All Orbit the Primary: A Statistical and Analytical Analysis
• Gravitational Collapse of Filamentary Magnetized Molecular Clouds
• Envelope Structure of Starless Core L694-2 Derived from a Near-Infrared Extinction Map
• Molecular Line Observations of Carbon-Chain-Producing Regions L1495B and L1521B
• Star Formation in Molecular Clouds
• Internal Motions in Starless Dense Cores
• Molecular Line Observations of a Carbon-Chain-Rich Core L492
• Unveiling the detailed density and velocity structures of the protostellar core B335
• Rotation of the pre-stellar core L1689B
• Molecular Emission Line Formation in Prestellar Cores
• A high resolution comparative study of the slowly contracting, starless cores, L694-2 and L1544
• Asymmetric Line Profiles in Dense Molecular Clumps Observed in MALT90: Evidence for Global Collapse
• The dynamical state of the First Hydrostatic Core Candidate Cha-MMS1
• Line Profiles of Cores within Clusters. III. What is the most reliable tracer of core collapse in dense clusters?
• A multi-transition molecular line study of inward motions towards massive star-forming cores
• Limits on Radio Continuum Emission from a Sample of Candidate Contracting Starless Cores
• Molecular line profiles as diagnostics of protostellar collapse: modelling the `blue asymmetry' in inside-out infall
• Confirmation of the VeLLO L1148-IRS: Star Formation at very low (Column) Density
• Physical properties of CO-dark molecular gas traced by C${}^{+}$
• Star-forming regions of the Aquila rift cloud complex. I. NH3 tracers of dense molecular cores
• On the fragmentation of filaments in a molecular cloud simulation
• Ambipolar Diffusion in Action: Transient C shock Structure and Prestellar Core Formation
• An Ammonia Spectral Map of the L1495-B218 Filaments in the Taurus Molecular Cloud: II CCS & HC${}_7$N Chemistry and Three Modes of Star Formation in the Filaments
• L1506: a prestellar core in the making
• Earliest Stages of Protocluster Formation: Substructure and Kinematics of Starless Cores in Orion
• Collapse and expansion in the bright-rimmed cloud SFO 11NE
• Distances to dense cores that contain Very Low Luminosity Objects
• TRAO Survey of the nearby filamentary molecular clouds, the universal nursery of stars (TRAO FUNS). II. Filaments and Dense cores in IC 5146
• A Low-mass Cold and Quiescent Core Population in a Massive Star Protocluster
• Star count analysis of the interstellar matter in the region of L1251
• A sensitive survey for water maser emission towards Bok globules using the Robledo 70m antenna
• Correlating Infall with Deuterium Fractionation in Dense Cores
• Far infrared observations of pre-protostellar sources in Lynds 183
• Velocity distribution of collapsing starless cores, L694-2 and L1197
• A large (~1 pc) contracting envelope around the prestellar core L1544
• Tracing the evolutionary stage of Bok globules: CCS and NH3
• Molecular Line Profiles from Contracting Dense Cores
• ALMA-IMF XIII: N${}_2$H${}^{+}$ kinematic analysis on the intermediate protocluster G353.41
• Inner Structure of Starless Core L694--2 Derived from Millimeter-Wave Interferometry
• Starless Cloud Core L1517B in Envelope Expansion with Core Collapse
• Spitzer Observations of L429: A Near-collapse or Collapsing Starless Core
• Far-infrared/sub-millimetre properties of pre-stellar cores L1521E, L1521F and L1689B as revealed by the Herschel SPIRE instrument -- I. Central positions
• CO Outflow Survey of 68 Very Low Luminosity Objects: a Search for Proto-Brown Dwarf Candidates
• ATOMS: ALMA Three-millimeter Observations of Massive Star-forming regions -- VI. On the formation of the "L" type filament in G286.21+0.17
• First Sub-pc Sale Mapping of Magnetic Fields in the Vicinity of a Very Low Luminosity Object, L1521F-IRS
• Infall/Expansion Velocities in the Low-Mass Dense Cores L492, L694-2, and L1521F: Dependence on Position and Molecular Tracer
• CS Depletion in Prestellar Cores
• Distance, magnetic field and kinematics of a filamentary cloud LDN 1157
• Alignment of dense molecular core morphology and velocity gradients with ambient magnetic fields
• Role of Filamentary Structures in the Formation of Two Dense Cores, L1544 and L694-2
• The Effects of Cosmic Rays on the Chemistry of Dense Cores
• Chemical tracers in proto-brown dwarfs: CO, ortho-H${}_2$CO, para-H${}_2$CO, HCO${}^{+}$, CS observations
• The Approach to Collapse of Molecular Clouds
• A Catalog of Molecular Clumps and Cores with Infall Signatures
• Molecular Tracers of Embedded Star Formation in Ophiuchus
• On the internal dynamics of starless cores: stability of starless cores with internal motions and collapse dynamics
• The initial magnetic criticality of prestellar cores
• Illuminating a tadpole's metamorphosis III: quantifying past and present environmental impact
• Core orientations and magnetic fields in isolated molecular clouds
• Detection of Two Carbon-Chain-Rich Cores; CB130-3 and L673-SMM4
• Nobeyama Survey of Inward Motions toward Cores in Orion Identified by SCUBA-2
• The Haystack Telescope as an Astronomical Instrument
• Millimetre Science with the Upgraded Australia Telescope
• On the role of magnetic fields in star formation
• Dense Molecular Cores Being Externally Heated
• Differences in chemical evolution between isolated and embedded prestellar cores
• Prestellar Cores in Turbulent Clouds: Numerical Modeling and Evolution to Collapse
• Physicochemical models: source-tailored or generic?
• Line emission from filaments in molecular clouds
• CLOVER: Convnet Line-fitting Of Velocities in Emission-line Regions
• Investigating the effects of chemistry on molecular line profiles of infalling low mass cores
• Prestellar Cores in Turbulent Clouds: Properties of Critical Cores
• Deuterium fractionation of the starless core L 1498
• The future of low-mass condensations in a core of molecular cloud
• Cooling Flows of Self-Gravitating, Rotating, Viscous Systems
• Why do some cores remain starless ?