Clump Lifetimes and the Initial Mass Function

Abstract

Recent studies of dense clumps/cores in a number of regions of low-mass star formation have shown that the mass distribution of these clumps closely resembles the initial mass function (IMF) of field stars. One possible interpretation of these observations is that we are witnessing the fragmentation of the clouds into the IMF, and the observed clumps are bound pre-stellar cores. In this paper, we highlight a potential difficulty in this interpretation, namely that clumps of varying mass are likely to have systematically varying lifetimes. This timescale problem can effectively destroy the similarity bewteen the clump and stellar mass functions, such that a stellar-like clump mass function (CMF) results in a much steeper stellar IMF. We also discuss some ways in which this problem may be avoided.

7 pages, 3 figures, accepted to MNRAS

References in corpus (29)

• Control of star formation by supersonic turbulence
• The Stellar IMF from Turbulent Fragmentation
• Competitive accretion in embedded stellar cluster
• The Universality of the Stellar IMF
• The mass function of dense molecular cores and the origin of the IMF
• A High Order Godunov Scheme with Constrained Transport and Adaptive Mesh Refinement for Astrophysical MHD
• Gravitational Collapse in Turbulent Molecular Clouds. I. Gasdynamical Turbulence
• Star formation through gravitational collapse and competitive accretion
• Star formation in clusters: a survey of compact mm-wave sources in the Serpens core
• The "Mysterious" Origin of Brown Dwarfs
• The Formation of Stellar Clusters: Mass Spectra from Turbulent Molecular Cloud Fragmentation
• Accretion in stellar clusters and the IMF
• Molecular cloud evolution. I. Molecular cloud and thin CNM sheet formation
• Gravitational Collapse in Turbulent Molecular Clouds. II. Magnetohydrodynamical Turbulence
• Simulating star formation in molecular cloud cores I. The influence of low levels of turbulence on fragmentation and multiplicity
• A SCUBA survey of Orion, the low-mass end of the core mass function
• Two regimes of Turbulent Fragmentation and the stellar IMF from Primordial to Present Day Star Formation
• Quiescent and coherent cores from gravoturbulent fragmentation
• Supersonic Turbulence and the Fragmentation of a Cold Medium
• A VLT/NACO Survey for Triple and Quadruple Systems among Visual Pre-Main Sequence Binaries
• Simulating star formation in molecular cores II. The effects of different levels of turbulence
• Multiple protostellar systems. I. A deep near infrared survey of Taurus and Ophiuchus protostellar objects
• Ambipolar-Diffusion Timescale, Star-Formation Timescale, and the Ages of Molecular Clouds: Is There a Discrepancy?
• The Formation of Star Clusters I: 3D Simulations of Hydrodynamic Turbulence
• Large Area Mapping at 850 Microns. IV. Analysis of the Clump Distribution in the Orion B South Molecular Cloud
• The Mass Spectra of Cores in Turbulent Molecular Clouds and Implications for the Initial Mass Function
• The dependence of the sub-stellar IMF on the initial conditions for star formation
• The structure of self-gravitating clouds
• Clumpy shocks and the clump mass function

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• Star Formation in the Milky Way and Nearby Galaxies
• The Spitzer c2d Legacy Results: Star Formation Rates and Efficiencies; Evolution and Lifetimes
• The Big Problems in Star Formation: the Star Formation Rate, Stellar Clustering, and the Initial Mass Function
• Star formation in Perseus - V. Outflows detected by HARP
• The ALMA Survey of 70 $\mu$m dark High-mass clumps in Early Stages (ASHES). I. Pilot Survey: Clump Fragmentation
• Limiting Accretion onto Massive Stars by Fragmentation-Induced Starvation
• A census of dense cores in the Aquila cloud complex: SPIRE/PACS observations from the Herschel Gould Belt survey
• The Stellar IMF, Core Mass Function, & The Last-Crossing Distribution
• Analytical theory for the initial mass function: II. Properties of the flow
• The unexpectedly large proportion of high-mass star-forming cores in a Galactic mini-starburst
• Radiation Feedback, Fragmentation, and the Environmental Dependence of the Initial Mass Function
• Analytical theory for the initial mass function: III time dependence and star formation rate
• On the Constancy of the Characteristic Mass of Young Stars
• Fragmentation in Molecular Clouds and its connection to the IMF
• Gravitational Collapse and Filament Formation: Comparison with the Pipe Nebula
• Importance of the Initial Conditions for Star Formation - II. Fragmentation Induced Starvation and Accretion Shielding
• The relationship between the prestellar core mass function and the stellar initial mass function
• The Complex Distribution of Recently Formed Stars. Bimodal Stellar Clustering in the Star-Forming Region NGC 346
• Unbound Young Stellar Systems: Star Formation on the loose
• Bondi-Hoyle-Littleton accretion and the upper mass stellar IMF
• The star formation efficiency and its relation to variations in the initial mass function
• The Core Mass Function in the Massive Protocluster G286.21+0.17 revealed by ALMA
• ALMA-IMF. V. Prestellar and protostellar core populations in the W43 cloud complex
• The Protostellar Mass Function
• The Origin of the Stellar Mass Distribution and Multiplicity
• Mapping the core mass function to the initial mass function
• On the Evolution of the Dense Core Mass Function
• The observable prestellar phase of the IMF
• Numerical and semi-analytic core mass distributions in supersonic isothermal turbulence
• Mass-loss and expansion of ultra compact dwarf galaxies through gas expulsion and stellar evolution for top-heavy stellar initial mass functions
• The IMF and multiplicity of stars from gravity, turbulence, magnetic fields, radiation and outflow feedback
• Star Formation in Molecular Clouds
• Pre-supernova feedback sets the star cluster mass function to a power law and reduces the cluster formation efficiency
• The IMF as a function of supersonic turbulence
• The properties of SCUBA cores in the Perseus molecular cloud: the bias of clump-finding algorithms
• Mapping the core mass function onto the stellar IMF: multiplicity matters
• LABOCA 870 micron dust continuum mapping of selected infrared-dark cloud regions in the Galactic plane
• Stellar and substellar initial mass function: a model that implements gravoturbulent fragmentation and accretion
• The Core Mass Function in the Orion Nebula Cluster Region: What Determines the Final Stellar Masses?
• The highly variable time evolution of star-forming cores identified with dendrograms
• What does a universal IMF imply about star formation?
• Protostar mass functions in young clusters
• Mass Functions in Fractal Clouds: The Role of Cloud Structure in the Stellar Initial Mass Function
• On the emergent System Mass Function: the contest between accretion and fragmentation
• A submillimetre survey of the kinematics of the Perseus molecular cloud - III. Clump kinematics
• Spatially associated clump populations in Rosette from CO and dust maps
• HII regions and high-mass starless clump candidates I: Catalogs and properties
• Clump mass function at an early stage of molecular cloud evolution: I. A statistical approach
• The CMF as provenance of the stellar IMF ?
• Models for the Formation of Massive Stars
• Fragmentation and Evolution of Molecular Clouds. III: The Effect of Dust and Gas Energetics
• Theories of the initial mass function
• Robustness of Synthetic Observations in Producing Observed Core Properties: Predictions for the TolTEC Clouds to Cores Legacy Survey
• The Effect of Magnetic Fields and Ambipolar Diffusion on Core Mass Functions
• Formation of low-mass stars and brown dwarfs
• Star Formation in Molecular Clouds?
• Low-mass Star Formation: Observations
• Empirical formulae to describe some physical properties of small groups of protogalaxies with multiplicity
• The fragmentation properties of massive star-forming regions in 30Dor-10 at 2000 au resolution
• Statistical mass function of prestellar cores from the density distribution of their natal clouds