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arXiv · 2610.16805

Evidence for Hierarchical Turbulent Scaling in Nearby Star-Forming Galaxies

Luna Maria Scipio·Fernando A. N. Santos·Jay Armas
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Abstract

We find recurring signatures of intermittency in molecular-gas velocities from cloud to galactic scales. In 31 selected galaxies from PHANGS-ALMA, velocity-centroid exponents through sixth order show nonlinear order dependence and nearly linear relations between consecutive exponents across galaxies. Positive estimated offsets from single-exponent scaling occur in all 52 galaxies with a valid power law fit and 99 of 100 clouds. A generalized She-Leveque hierarchy accommodates these signatures, supporting a hierarchical description of turbulent scaling in molecular gas across these environments.

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Luna Maria Scipio, Fernando A. N. Santos, Jay Armas. 2026-10-12. Evidence for Hierarchical Turbulent Scaling in Nearby Star-Forming Galaxies. https://arxiv.org/abs/2610.16805

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