An ALMA study of hub-filament systems I. On the clump mass concentration within the most massive cores

Abstract

The physical processes behind the transfer of mass from parsec-scale clumps to massive-star-forming cores remain elusive. We investigate the relation between the clump morphology and the mass fraction that ends up in its most massive core (MMC) as a function of infrared brightness, i.e. a clump evolutionary tracer. Using ALMA 12 m and ACA we surveyed 6 infrared-dark hubs in 2.9mm continuum at $\sim$3" resolution. To put our sample into context, we also re-analysed published ALMA data from a sample of 29 high mass-surface density ATLASGAL sources. We characterise the size, mass, morphology, and infrared brightness of the clumps using Herschel and Spitzer data. Within the 6 newly observed hubs, we identify 67 cores, and find that the MMCs have masses between 15-911 ${\mathrm{M}}_{\odot }$ within a radius of 0.018-0.156 pc. The MMC of each hub contains 3-24% of the clump mass ($f_{\mathrm{MMC}}$), becoming 5-36% once core masses are normalised to the median core radius. Across the 35 clumps, we find no significant difference in the median $f_{\mathrm{MMC}}$ values of hub and non-hub systems, likely the consequence of a sample bias. However, we find that $f_{\mathrm{MMC}}$ is $\sim$7.9 times larger for infrared-dark clumps compared to infrared-bright ones. This factor increases up to $\sim$14.5 when comparing our sample of 6 infrared-dark hubs to infrared-bright clumps. We speculate that hub-filament systems efficiently concentrate mass within their MMC early on during its evolution. As clumps evolve, they grow in mass, but such growth does not lead to the formation of more massive MMCs.

15 pages, 9 figures

References in corpus (28)

• Array Programming with NumPy
• scikit-image: Image processing in Python
• Trigonometric Parallaxes of Massive Star Forming Regions: VI. Galactic Structure, Fundamental Parameters and Non-Circular Motions
• MAMBO Mapping of Spitzer c2d Small Clouds and Cores
• Structural Analysis of Molecular Clouds: Dendrograms
• Multi-Scale CLEAN deconvolution of radio synthesis images
• Filamentary structure of star-forming complexes
• The earliest phases of high-mass star formation: a 3 square degree millimeter continuum mapping of Cygnus X
• Identifying the Low Luminosity Population of Embedded Protostars in the c2d Observations of Clouds and Cores
• ATLASGAL --- towards a complete sample of massive star forming clumps
• A SCUBA survey of Orion, the low-mass end of the core mass function
• Properties of Hi-GAL clumps in the inner Galaxy]{The Hi-GAL compact source catalogue. I. The physical properties of the clumps in the inner Galaxy ($-71.0^{\circ }<\ell <67.0^{\circ }$)
• Limiting Accretion onto Massive Stars by Fragmentation-Induced Starvation
• Fragmentation of Molecular Clumps and Formation of Protocluster
• On the Structure of the Orion A Cloud and the Formation of the Orion Nebula Cluster
• Multi-temperature mapping of dust structures throughout the Galactic Plane using the PPMAP tool with Herschel Hi-GAL data
• The identification of filaments on far infrared and submillimiter images. Morphology, physical conditions and relation with star formation of filamentary structure
• Properties of the dense core population in Orion B as seen by the Herschel Gould Belt survey
• Investigating the Global Collapse of Filaments Using Smoothed Particle Hydrodynamics
• The Physical and chemical structure of Sagittarius B2 -- IV. Converging filaments in the high-mass cluster forming region Sgr B2(N)
• G11.92-0.61-MM2: A Bonafide Massive Prestellar Core?
• ALMA-IRDC: Dense gas mass distribution from cloud to core scales
• A dynamically young, gravitationally stable network of filaments in Orion B
• The accretion history of high-mass stars: An ArTéMiS pilot study of Infrared Dark Clouds
• Kinematics and Structure of Star-forming Regions: Insights from Cold Collapse Models
• GASTON: Galactic Star Formation with NIKA2. Evidence for the mass growth of star-forming clumps
• Continuity of accretion from clumps to Class 0 high-mass protostars in SDC335
• Tightening the belt: Constraining the mass and evolution in SDC335

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• ATOMS: ALMA Three-millimeter Observations of Massive Star-forming regions -- XV. Steady Accretion from Global Collapse to Core Feeding in Massive Hub-filament System SDC335
• Evidence of high-mass star formation through multi-scale mass accretion in hub-filament-system clouds
• The SQUALO project (Star formation in QUiescent And Luminous Objects) I: clump-fed accretion mechanism in high-mass star-forming objects
• The formation of massive stellar clusters in converging galactic flows with photoionisation
• Simultaneous evidence of edge collapse and hub-filament configurations: A rare case study of a Giant Molecular Filament G45.3+0.1
• Formation of the SDC13 Hub-Filament System: A Cloud-Cloud Collision Imprinted on The Multiscale Magnetic Field
• Low Mass Stars as Tracers of Star and Cluster Formation
• The dynamic centres of infrared-dark clouds and the formation of cores
• The widths of magnetised filaments in molecular clouds
• The origin of a universal filament width in molecular clouds
• Emergence of high-mass stars in complex fiber networks (EMERGE). I. Early ALMA Survey: observations and massive data reduction
• Atacama Large Aperture Submillimeter Telescope (AtLAST) Science: Our Galaxy
• The initial magnetic criticality of prestellar cores
• Emergence of high-mass stars in complex fiber networks (EMERGE) V. From filaments to spheroids: the origin of the hub-filament systems
• ALMAGAL VI. The spatial distribution of dense cores during the evolution of cluster-forming massive clump
• Differences in chemical evolution between isolated and embedded prestellar cores
• ALMAGAL V. Relations between the core populations and the parent clump physical properties
• A new phase of massive star formation? A luminous outflow cavity centred on an infrared quiet core
• Ionising feedback from an O star formed in a shock-compressed layer
• Line emission from filaments in molecular clouds
• Gas and star kinematics in cloud-cloud collisions
• The fragmentation properties of massive star-forming regions in 30Dor-10 at 2000 au resolution
• Evolution of compressed clouds formed by filament coalescence. I. Oblique collisions
• Properties of Contracting Massive Protostellar Cores