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arXiv · 2510.25436

Accelerating star formation of dense clumps

Xunchuan Liu
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Abstract

We present a statistical framework that establishes an accelerating star formation scenario for dense clumps using ATLASGAL and ALMAGAL samples. By employing the cumulative distribution function of dust temperature as a monotonic evolutionary indicator, we linearize clump evolution into a normalized timescale, enabling direct comparison across different samples. The virial mass of clumps increases exponentially with this normalized time, revealing an accelerating buildup of star-forming gas within protoclusters. The evolution of the maximum core mass further shows that the growth timescales of protoclusters and their embedded most massive protostars are comparable, implying a self-similar acceleration of star formation from the stellar to the protocluster scale. This unified framework naturally reproduces the observed evolution of luminosity, the core mass function, the mass growth of the most massive protostars, and the dense gas star formation law on clump scales, establishing a coherent picture of accelerating star formation across scales.

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Xunchuan Liu. 2025-10-29. Accelerating star formation of dense clumps. https://arxiv.org/abs/2510.25436

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