Star formation in evolving molecular clouds

Abstract

Molecular clouds are the principle stellar nurseries of our universe, keeping them in the focus of both observational and theoretical studies. From observations, some of the key properties of molecular clouds are well known but many questions regarding their evolution and star formation activity remain open. While numerical simulations feature a large number and complexity of involved physical processes, this plenty of effects may hide the fundamentals that determine the evolution of molecular clouds and enable the formation of stars. Purely analytical models, on the other hand, tend to suffer from rough approximations or a lack of completeness, limiting their predictive power. In this paper, we present a model that incorporates central concepts of astrophysics as well as reliable results from recent simulations of molecular clouds and their evolutionary paths. Based on that, we construct a self-consistent semi-analytical framework that describes the formation, evolution and star formation activity of molecular clouds, including a number of feedback effects to account for the complex processes inside those objects. The final equation system is solved numerically but at much lower computational expense than, e.g., hydrodynamical descriptions of comparable systems. The model presented in this paper agrees well with a broad range of observational results, showing that molecular cloud evolution can be understood as an interplay between accretion, global collapse, star formation and stellar feedback.

11 pages, 11 figures. Accepted for publication in A&A

References in corpus (45)

• A General Theory of Turbulence-Regulated Star Formation, From Spirals to ULIRGs
• The Stellar IMF from Turbulent Fragmentation
• The Formation of Massive Stars from Turbulent Cores
• Comparing the statistics of interstellar turbulence in simulations and observations: Solenoidal versus compressive turbulence forcing
• The Star Formation Rate of Turbulent Magnetized Clouds: Comparing Theory, Simulations, and Observations
• On the Star Formation Rates in Molecular Clouds
• Analytical theory for the initial mass function: CO clumps and prestellar cores
• The Millennium Arecibo 21-CM Absorption Line Survey. II. Properties of the Warm and Cold Neutral Media
• The Density Probability Distribution in Compressible Isothermal Turbulence: Solenoidal versus Compressive Forcing
• 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
• On the Star Formation Efficiency of Turbulent Magnetized Clouds
• Star Formation Efficiencies and Lifetimes of Giant Molecular Clouds in the Milky Way
• An Origin of Supersonic Motions in Interstellar Clouds
• The Equilibrium State of Molecular Regions in the Outer Galaxy
• One-Point Probability Distribution Functions of Supersonic Turbulent Flows in Self-Gravitating Media
• A Dying Universe: The Long Term Fate and Evolution of Astrophysical Objects
• The Second Survey of the Molecular Clouds in the Large Magellanic Cloud by NANTEN. II. Star Formation
• What controls star formation in the central 500 pc of the Galaxy?
• What determines the density structure of molecular clouds ? A case study of Orion B with Herschel
• Molecular Cloud Formation in Shock-Compressed Layers
• Before the first supernova: combined effects of HII regions and winds on molecular clouds
• Molecular cloud evolution. I. Molecular cloud and thin CNM sheet formation
• The Nature of the Dense Core Population in the Pipe Nebula: Thermal Cores Under Pressure
• Clump morphology and evolution in MHD simulations of molecular cloud formation
• Feedback from Winds and Supernovae in Massive Stellar Clusters. I: Hydrodynamics
• Limiting Accretion onto Massive Stars by Fragmentation-Induced Starvation
• Supernova Driving. I. The Origin of Molecular Cloud Turbulence
• On the evolution of the density pdf in strongly self-gravitating systems
• The California Molecular Cloud
• Supersonic Turbulence and the Fragmentation of a Cold Medium
• Understanding Spatial and Spectral Morphologies of Ultracompact H II Regions
• Understanding star formation in molecular clouds I. Effects of line-of-sight contamination on the column density structure
• Molecular Cloud Evolution III. Accretion vs. stellar feedback
• Turbulence sets the initial conditions for star formation in high-pressure environments
• Stellar feedback efficiencies: supernovae versus stellar winds
• Importance of the Initial Conditions for Star Formation - II. Fragmentation Induced Starvation and Accretion Shielding
• Molecular and Atomic Gas in the Large Magellanic Cloud II. Three-dimensional Correlation between CO and HI
• Dense cores in the Pipe Nebula: An improved core mass function
• An Evolutionary Model for Collapsing Molecular Clouds and Their Star Formation Activity
• Can Protostellar Jets Drive Supersonic Turbulence in Molecular Clouds?
• The Free-Fall time of finite Sheets and Filaments
• Supernova Feedback in Molecular Clouds: Global Evolution and Dynamics
• Shock interactions, turbulence, and the origin of the stellar mass spectrum
• Magnetohydrodynamic simulations of mechanical stellar feedback in a sheet-like molecular cloud
• Cluster formation in molecular clouds: I. stellar populations, star formation rates, and ionizing radiation

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