Filamentary structure of star-forming complexes

TL;DR

This paper investigates the filamentary structures in star-forming regions, proposing a model where initial gas compression leads to hub-filament systems that resemble observed stellar groups and clouds.

Contribution

It introduces a new model explaining the formation of hub-filament structures through gas compression and gravitational collapse, aligning with observed properties.

Findings

Model predicts filamentary structures similar to observations

Hub-filament systems form from compressed clumpy gas

Structures resemble observed star-forming regions

Abstract

The nearest young stellar groups are associated with "hubs" of column density exceeding 10^22 cm^-2, according to recent observations. These hubs radiate multiple "filaments" of parsec length, having lower column density and fewer stars. Systems with many filaments tend to have parallel filaments with similar spacing. Such "hub-filament structure" is associated with all of the nine young stellar groups within 300 pc, forming low-mass stars. Similar properties are seen in infrared dark clouds forming more massive stars. In a new model, an initial clump in a uniform medium is compressed into a self-gravitating, modulated layer. The outer layer resembles the modulated equilibrium of Schmid-Burgk (1967) with nearly parallel filaments. The filaments converge onto the compressed clump, which collapses to form stars with high efficiency. The initial medium and condensations have densities similar to those in nearby star-forming clouds and clumps. The predicted structures resemble observed hub-filament systems in their size, shape, and column density, and in the appearance of their filaments. These results suggest that hub-filament structure associated with young stellar groups may arise from compression of clumpy gas in molecular clouds.