README.md

2025LZGY

Codex/ChatGPT (July 2026)

Summary

This study characterizes turbulence generated internally by three-dimensional resistive magnetohydrodynamic reconnection rather than imposed by external forcing. Simulations with the AMUN code vary explicit resistivity, initial perturbation amplitude, guide field, and isothermal versus adiabatic closure. Power spectra, scale-dependent anisotropy, compressive--solenoidal decomposition, and structure functions describe the resulting cascade. Across the tested cases, velocity follows a Kolmogorov-like $E_v(k)\propto k^{-5/3}$ spectrum, while magnetic energy is steeper and can approach $k^{-8/3}$ in the direction most affected by anisotropy. Resistivity and perturbation amplitude have little effect on these statistical signatures. Most cases develop anisotropic cascades broadly consistent with strong-MHD-turbulence expectations, but a guide field produces an approximately isotropic cascade in these simulations. Adiabatic runs are nearly incompressible and dominated by solenoidal velocity energy. The velocity field is also more intermittent than the magnetic field, reversing the ordering commonly reported for homogeneous MHD turbulence. The conclusions are limited by numerical resolution: small-scale anisotropy may be contaminated by numerical dissipation, and the guide-field result differs from some externally driven studies and requires further high-resolution testing.

Contributions

1. Measured multiple statistical properties of self-driven reconnection turbulence in a common three-dimensional simulation framework.
2. Identified a robust combination of Kolmogorov-like velocity spectra and substantially steeper magnetic spectra.
3. Showed that the tested spectral and anisotropy signatures are insensitive to explicit resistivity and initial perturbation amplitude.
4. Found a guide-field-induced transition to an approximately isotropic cascade within the studied setup.
5. Established quasi-incompressible, solenoidal dynamics in adiabatic runs and stronger velocity than magnetic intermittency.