A closer look at the "characteristic" width of molecular cloud filaments

Abstract

Filaments in Herschel molecular cloud images are found to exhibit a "characteristic width". This finding is in tension with spatial power spectra of the data, which show no indication of this characteristic scale. We demonstrate that this discrepancy is a result of the methodology adopted for measuring filament widths. First, we perform the previously used analysis technique on artificial scale-free data, and obtain a peaked width distribution of filament-like structures. Next, we repeat the analysis on three Herschel maps and reproduce the narrow distribution of widths found in previous studies $-$ when considering the average width of each filament. However, the distribution of widths measured at all points along a filament spine is broader than the distribution of mean filament widths, indicating that the narrow spread (interpreted as a "characteristic" width) results from averaging. Furthermore, the width is found to vary significantly from one end of a filament to the other. Therefore, the previously identified peak at 0.1 pc cannot be understood as representing the typical width of filaments. We find an alternative explanation by modelling the observed width distribution as a truncated power-law distribution, sampled with uncertainties. The position of the peak is connected to the lower truncation scale and is likely set by the choice of parameters used in measuring filament widths. We conclude that a "characteristic" width of filaments is not supported by the available data.

15 pages (incl. appendices), 16 figures, accepted to MNRAS

References in corpus (10)

• On the nature of star-forming filaments: I. Filament morphologies
• CARMA Large Area Star Formation Survey: Observational Analysis of Filaments in the Serpens South Molecular Cloud
• Herschel's view of the large-scale structure in the Chamaeleon dark clouds
• Probing interstellar turbulence in cirrus with deep optical imaging: no sign of energy dissipation at 0.01 pc scale
• Investigating the structure and fragmentation of a highly filamentary IRDC
• Unveiling the Early-Stage Anatomy of a Protocluster Hub with ALMA
• The magnetic field and dust filaments in the Polaris Flare
• Collective outflow from a small multiple stellar system
• A Magnetic Ribbon Model for Star-Forming Filaments
• The Star Formation Law in a Multifractal ISM

Cited by in corpus (38)

• Filamentary Accretion Flows in the Infrared Dark Cloud G14.225-0.506 Revealed by ALMA
• On the Three-Dimensional Structure of Local Molecular Clouds
• From diffuse gas to dense molecular cloud cores
• The CARMA-NRO Orion Survey: The filamentary structure as seen in C${}^{18}$O emission
• How do stars gain their mass? A JCMT/SCUBA-2 Transient Survey of Protostars in Nearby Star Forming Regions
• Interstellar filaments and star formation
• Zooming in on Individual Star Formation: Low- and High-mass Stars
• Formation of the Musca filament: Evidence for asymmetries in the accretion flow due to a cloud-cloud collision
• Magnetized interstellar molecular clouds: II. The Large-Scale Structure and Dynamics of Filamentary Molecular Clouds
• The width of Herschel filaments varies with distance
• A dynamically young, gravitationally stable network of filaments in Orion B
• Witnessing the fragmentation of a filament into prestellar cores in Orion B/NGC 2024
• Dissecting the super-critical filaments embedded in the 0.5 pc subsonic region of Barnard 5
• Statistical model for filamentary structures of molecular clouds -- The modified multiplicative random cascade model and its multifractal nature
• Modelling the chemistry of star-forming filaments - II. Testing filament characteristics with synthetic observations
• How the power spectrum of dust continuum images may hide the presence of a characteristic filament width
• The Cygnus Allscale Survey of Chemistry and Dynamical Environments: CASCADE: Overview and first results toward DR20 from the Max Planck IRAM Observatory program (MIOP)
• The widths of magnetised filaments in molecular clouds
• Dust in the Wind with Resonant Drag Instabilities: I. The Dynamics of Dust-Driven Outflows in GMCs and HII Regions
• The origin of a universal filament width in molecular clouds
• Synthetic line and continuum observations of simulated turbulent clouds: the apparent widths of filaments
• Atacama Large Aperture Submillimeter Telescope (AtLAST) Science: Our Galaxy
• The discovery of the largest gas filament in our Galaxy, or a new spiral arm?
• Velocity-Coherent Substructure in TMC-1: Inflow and Fragmentation
• Non-ideal magnetohydrodynamics of self-gravitating filaments
• Emergence of high-mass stars in complex fiber networks (EMERGE) IV. Environmental dependence of the fiber widths
• Symmetry properties and widths of the filamentary structures in the Orion A giant molecular cloud
• A systematic bias in fitting the surface-density profiles of interstellar filaments
• Line emission from filaments in molecular clouds
• Non-parametric Bayesian reconstruction of Galactic magnetic fields using Information Field Theory: The inclusion of line-of-sight information in ultra-high energy cosmic ray backtracking
• Comparison of Herschel and ArTéMiS observations of massive filaments
• Investigations of MWISP Filaments. I. Filament Identification and Analysis Algorithms, and Source Catalogue
• Scale-dependent surface and volume density properties of filaments in molecular clouds
• Sutra : An integrated framework for identification and characterization of filaments in the interstellar medium
• Interstellar filament detection and characterization: methods and implications for studies of magnetized interstellar medium
• The influence of magnetic fields in Cloud-Cloud Collisions
• A complete survey of filaments in Cygnus X
• Direct power spectral density estimation from structure functions without Fourier transforms