Merging Filaments I: A race against collapse

Abstract

The interstellar medium is characterised by an intricate filamentary network which exhibits complex structures. These show a variety of different shapes (e.g. junctions, rings, etc.) deviating strongly from the usually assumed cylindrical shape. A possible formation mechanism are filament mergers which we analyse in this study. Indeed, the proximity of filaments in networks suggests mergers to be rather likely. As the merger has to be faster than the end dominated collapse of the filament along its major axis we expect three possible results: (a) The filaments collapse before a merger can happen, (b) the merged filamentary complex shows already signs of cores at the edges or (c) the filaments merge into a structure which is not end-dominated. We develop an analytic formula for the merging and core-formation timescale at the edge and validate our model via hydrodynamical simulations with the adaptive-mesh-refinement-code RAMSES. This allows us to predict the outcome of a filament merger, given different initial conditions which are the initial distance and the respective line-masses of each filament as well as their relative velocities.

arXiv comment10 pages, 11 figures

References in corpus (40)

• Cosmological Hydrodynamics with Adaptive Mesh Refinement: a new high resolution code called RAMSES
• From filamentary clouds to prestellar cores to the stellar IMF: Initial highlights from the Herschel Gould Belt survey
• Clouds, filaments and protostars: the Herschel Hi-GAL Milky Way
• Characterizing interstellar filaments with Herschel in IC5146
• Cores, filaments, and bundles: hierarchical core formation in the L1495/B213 Taurus region
• The initial conditions of stellar protocluster formation. I. A catalogue of Spitzer dark clouds
• An ALMA study of the Orion Integral Filament: I. Evidence for narrow fibers in a massive cloud
• From Filamentary Networks to Dense Cores in Molecular Clouds: Toward a New Paradigm for Star Formation
• Characterizing the properties of nearby molecular filaments observed with Herschel
• Dense core formation by fragmentation of velocity-coherent filaments in L1517
• A census of dense cores in the Aquila cloud complex: SPIRE/PACS observations from the Herschel Gould Belt survey
• Collapse and Fragmentation in Finite Sheets
• On the nature of star-forming filaments: I. Filament morphologies
• Chains of dense cores in the Taurus L1495/B213 complex
• On the Structure of the Orion A Cloud and the Formation of the Orion Nebula Cluster
• Helical Fields and Filamentary Molecular Clouds II - Axisymmetric Stability and Fragmentation
• Physical properties of interstellar filaments
• The Bones of the Milky Way
• Cloud-cloud collisions and triggered star formation
• Dust Extinction and Molecular Cloud Structure: L977
• Filamentary fragmentation in a turbulent medium
• Aspect Ratio Dependence of the Free-Fall Time for Non-Spherical Symmetries
• Gravitational fragmentation caught in the act: the filamentary Musca molecular cloud
• Cluster Formation Triggered by Filament Collisions in Serpens South
• The Free-Fall time of finite Sheets and Filaments
• Investigating the Global Collapse of Filaments Using Smoothed Particle Hydrodynamics
• A possible link between the power spectrum of interstellar filaments and the origin of the prestellar core mass function
• Structure and Fragmentation of a high line-mass filament: Nessie
• Observational signatures of end-dominated collapse in the S242 filamentary structure
• Oscillating Filaments: I - Oscillation and Geometrical Fragmentation
• On the fragmentation of filaments in a molecular cloud simulation
• Edge collapse and subsequent longitudinal accretion in Filament S242
• Star-forming sites IC 446 and IC 447: an outcome of end-dominated collapse of Monoceros R1 filament
• Accretion driven turbulence in filaments II: Effects of self-gravity
• Non-linear dense core formation in the dark cloud L1517
• LABOCA mapping of the infrared dark cloud MSXDC G304.74+01.32
• Formation of dense structures induced by filament collisions. Correlation of density, kinematics and magnetic field in the Pipe nebula
• Dissecting the super-critical filaments embedded in the 0.5 pc subsonic region of Barnard 5
• Accretion driven turbulence in filaments I: Non-gravitational accretion
• From Filaments to Oscillating Starless Cores

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