A possible link between the power spectrum of interstellar filaments and the origin of the prestellar core mass function

Abstract

Two major features of the prestellar CMF are: 1) a broad peak below 1 Msun, presumably corresponding to a mean gravitational fragmentation scale, and 2) a characteristic power-law slope, very similar to the Salpeter slope of the stellar initial mass function (IMF) at the high-mass end. While recent Herschel observations have shown that the peak of the prestellar CMF is close to the thermal Jeans mass in marginally supercritical filaments, the origin of the power-law tail of the CMF/IMF at the high-mass end is less clear. Inutsuka (2001) proposed a theoretical scenario in which the origin of the power-law tail can be understood as resulting from the growth of an initial spectrum of density perturbations seeded along the long axis of filaments by interstellar turbulence. Here, we report the statistical properties of the line-mass fluctuations of filaments in nearby molecular clouds observed with Herschel using a 1-D power spectrum analysis. The observed filament power spectra were fitted by a power-law function $(P_{true}(s)\propto s^{\alpha })$ after removing the effect of beam convolution at small scales. A Gaussian-like distribution of power-spectrum slopes was found centered at -1.6, close to that of the one-dimensional velocity power spectrum generated by subsonic Kolomogorov turbulence (-1.67). An empirical correlation, $P^{0.5}(s_0)\propto <N_{{\mathrm{H}}_2}{>}^{1.4\pm 0.1}$, was also found between the amplitude of each filament power spectrum $P(s_0)$ and the mean column density along the filament $<N_{{\mathrm{H}}_2}>$. Finally, the dispersion of line-mass fluctuations along each filament ${\sigma }_{{\mathrm{M}}_{\mathrm{line}}}$ was found to scale with the physical length $L$ of the filament, roughly as ${\sigma }_{M_{line}}\propto L^{0.7}$. Overall, our results are consistent with the suggestion that the bulk of the CMF/IMF results from the gravitational fragmentation of filaments.

arXiv comment10 pages, 12 figures, Accepted for publication in Astronomy and Astrophysics journal

References in corpus (37)

• Herschel Space Observatory - An ESA facility for far-infrared and submillimetre astronomy
• The Photodetector Array Camera and Spectrometer (PACS) on the Herschel Space Observatory
• The Herschel-SPIRE instrument and its in-flight performance
• From filamentary clouds to prestellar cores to the stellar IMF: Initial highlights from the Herschel Gould Belt survey
• The Stellar IMF from Turbulent Fragmentation
• Comparing the statistics of interstellar turbulence in simulations and observations: Solenoidal versus compressive turbulence forcing
• Clouds, filaments and protostars: the Herschel Hi-GAL Milky Way
• Characterizing interstellar filaments with Herschel in IC5146
• On the Star Formation Rates in Molecular Clouds
• The Statistics of Supersonic Isothermal Turbulence
• Herschel view of the Taurus B211/3 filament and striations: Evidence of filamentary growth?
• Analytical theory for the initial mass function: CO clumps and prestellar cores
• The Star Formation Rate and Gas Surface Density Relation in the Milky Way: Implications for Extragalactic Studies
• The mass function of dense molecular cores and the origin of the IMF
• Global collapse of molecular clouds as a formation mechanism for the most massive stars
• The earliest phases of high-mass star formation: a 3 square degree millimeter continuum mapping of Cygnus X
• The Aquila prestellar core population revealed by Herschel
• The Turbulent Shock Origin of Proto--Stellar Cores
• The persistent cosmic web and its filamentary structure II: Illustrations
• Scanamorphos: a map-making software for Herschel and similar scanning bolometer arrays
• The Formation and Destruction of Molecular Clouds and Galactic Star Formation
• Filaments and ridges in Vela C revealed by Herschel: from low-mass to high-mass star-forming sites
• The Fractal Density Structure in Supersonic Isothermal Turbulence: Solenoidal versus Compressive Energy Injection
• 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
• Herschel-SPIRE observations of the Polaris flare : structure of the diffuse interstellar medium at the sub-parsec scale
• The Stellar IMF, Core Mass Function, & The Last-Crossing Distribution
• On the origin of non self-gravitating filaments in the ISM
• Reconstructing the density and temperature structure of prestellar cores from $Herschel$ data: A case study for B68 and L1689B
• Formation and evolution of interstellar filaments; Hints from velocity dispersion measurements
• The Pipe Nebula as seen with Herschel: Formation of filamentary structures by large-scale compression ?
• Variations of the stellar initial mass function in the progenitors of massive early-type galaxies and in extreme starburst environments
• The first release of data from the Herschel ATLAS: the SPIRE images
• A turbulent MHD model for molecular clouds and a new method of accretion on to star-forming cores
• The Cloud-in-Cloud Problem in the Press-Schechter Formalism of Hierarchical Structure Formation
• Direct Estimate of Cirrus Noise in Herschel Hi-GAL Images
• BLAST05: Power Spectra of Bright Galactic Cirrus at Submillimeter Wavelengths

Cited by in corpus (35)

• Characterizing the properties of nearby molecular filaments observed with Herschel
• The link between turbulence, magnetic fields, filaments, and star formation in the Central Molecular Zone cloud G0.253+0.016
• On the universality of interstellar filaments: theory meets simulations and observations
• Characterizing filaments in regions of high-mass star formation: High-resolution submilimeter imaging of the massive star-forming complex NGC 6334 with ArTéMiS
• Resolving the fragmentation of high line-mass filaments with ALMA: the integral shaped filament in Orion A
• Dust polarized emission observations of NGC 6334; BISTRO reveals the details of the complex but organized magnetic field structure of the high-mass star-forming hub-filament network
• The role of molecular filaments in the origin of the prestellar core mass function and stellar initial mass function
• Perturbation growth in accreting filaments
• Interstellar filaments and star formation
• Understanding star formation in molecular clouds IV. Column density PDFs from quiescent to massive molecular clouds
• An ALMA study of hub-filament systems I. On the clump mass concentration within the most massive cores
• The Origin of the Stellar Mass Distribution and Multiplicity
• Evolutionary Description of Giant Molecular Cloud Mass Functions on Galactic Disks
• Physical properties of the ambient medium and of dense cores in the Perseus star-forming region derived from Herschel Gould Belt Survey observations
• Fragmentation of star-forming filaments in the X-shape Nebula of the California molecular cloud
• Herschel Gould Belt Survey Observations of Dense Cores in the Cepheus Flare Clouds
• Analytical core mass function (CMF) from filaments: Under which circumstances can filament fragmentation reproduce the CMF?
• Star Formation Induced by Cloud-Cloud Collisions and Galactic Giant Molecular Cloud Evolution
• The core and stellar mass functions in massive collapsing filaments
• An Origin for the Angular Momentum of Molecular Cloud Cores: a Prediction from Filament Fragmentation
• Accretion driven turbulence in filaments II: Effects of self-gravity
• Velocity structure of the 50 pc-long NGC 6334 filamentary cloud: Hints of multiple compressions and their impact on the cloud properties?
• Merging Filaments I: A race against collapse
• How the power spectrum of dust continuum images may hide the presence of a characteristic filament width
• CARMA-NRO Orion Survey: unbiased survey of dense cores and core mass functions in Orion A
• Evolution of the Angular Momentum of Molecular Cloud Cores Formed from Filament Fragmentation
• Turbulence and Accretion: a High-resolution Study of the B5 Filaments
• Description of turbulent dynamics in the interstellar medium: multifractal/microcanonical analysis I. Application to Herschel observations of the Musca filament
• Filament collapse: a two phase process
• Fates of the dense cores formed by fragmentation of filaments: do they fragment again or not?
• Probing the filamentary nature of star formation in the California giant molecular cloud
• The isothermal evolution of a shock-filament interaction
• Filament fragmentation: Density gradients suppress end dominated collapse
• Radiation Hydrodynamics Simulations of Spherical Protostellar Collapse for Very Low Mass Objects
• A Deep Neural Network Approach to Compact Source Removal