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arXiv · 2512.00983

A robust empirical relationship between speed and turbulence energy in the near-Earth solar wind

Rohit Chhiber·Yanwen Wang·Manuel E. Cuesta·Jiaming Wang·Sohom Roy
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Abstract

The connection between turbulence and solar-wind acceleration, long known in space physics, is further developed in this Letter by establishing a robust empirical law that relates the bulk-flow speed to the magnetohydrodynamic-scale fluctuation energy in the plasma. The model is based on analysis of twenty-five years of near-Earth observations by NASA's Advanced Composition Explorer. It provides a simple way to estimate turbulence energy from low-resolution speed data -- a practical approach that may be of utility when high-resolution measurements or advanced turbulence models are unavailable. Potential heliospheric applications include space-weather forecasting operations, remote imaging datasets, and energetic-particle transport models that require turbulence amplitudes to specify diffusion parameters.

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Rohit Chhiber, Yanwen Wang, Manuel E. Cuesta, Jiaming Wang, Sohom Roy. 2025-11-30. A robust empirical relationship between speed and turbulence energy in the near-Earth solar wind. https://arxiv.org/abs/2512.00983

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