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arXiv · 2604.14093

A Salpeter-like filament linear density function across nearby molecular clouds

Guo-Yin Zhang·Alexander Men'shchikov·Jin-Zeng Li
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Abstract

The high-mass slope of the stellar initial mass function (IMF), first measured by Salpeter in 1955, appears nearly universal across star-forming environments, yet its physical origin remains unknown. Using the multiscale extraction method getsf, we measure the filament linear density function (FLDF) across seven nearby molecular clouds ($140-920$ pc) spanning a wide range of star-forming activity. The FLDF slope shows no systematic trend with spatial scale. Combining all clouds and scales, the composite FLDF follows a power law ${\rm d}N/{\rm d}\log\Lambda \propto \Lambda^{-\alpha}$ with $\alpha \approx 1.40$, close to the Salpeter value of $1.35$, and the same composite slope is found in every cloud despite an order-of-magnitude spread in their supercritical-filament fractions. The close similarity between the composite FLDF slope and the Salpeter value suggests a possible physical link between the hierarchical filamentary structure of the cold interstellar medium and the IMF.

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Guo-Yin Zhang, Alexander Men'shchikov, Jin-Zeng Li. 2026-04-15. A Salpeter-like filament linear density function across nearby molecular clouds. https://arxiv.org/abs/2604.14093

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