Improved Energy Fractions for Model Slab and Two-dimensional Interplanetary Turbulence
- 1University of New Hampshire
- 2Southwest Research Institute
Abstract
The distribution of energy within interplanetary turbulence has been modeled with a slab part with wavevectors along the background magnetic field B ₀ and a 2D part with wavevectors perpendicular to B ₀ . J. W. Bieber et al. (1996) ascertained the amount of magnetic energy in the slabs relative to the total perpendicular magnetic energy observed by determining the ratio of the spectral amplitude squared values that characterize the spectra of the fluctuating magnetic field components that are perpendicular to B ₀ and each other. Integrals over the spectrum of the slab and 2D model were made to establish how the spectrum would appear to a spacecraft. In the present analysis, certain factors that belong to the solution of the integrals are not in the formulas published in J. W. Bieber et al. (1996). The missing factors are provided here. A generalization is made to account for energy in all directions for both slab and 2D turbulence, separately, and for a parallel magnetic field component associated with the 2D turbulence. With this generalization, the fraction of energy in slabs is reduced by 30%–40% in relative change, which makes the 2D turbulence generally more significant in the dissipation range. For individual intervals, the accuracy of the energy fraction can be enhanced by limiting observations to a particular range of angles between the sampling direction and B ₀ . A method to obtain accurate spectra fit parameters is demonstrated with an example.
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BibTeX
@article{vasquez2026improved,
title = {{Improved Energy Fractions for Model Slab and Two-dimensional Interplanetary Turbulence}},
author = {Bernard J. Vasquez and Charles W. Smith and Roy B. Torbert},
journal = {The Astrophysical Journal Supplement Series},
year = {2026},
month = oct,
doi = {10.3847/1538-4365/aeaa3d},
url = {https://iopscience.iop.org/article/10.3847/1538-4365/aeaa3d},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Improved Energy Fractions for Model Slab and Two-dimensional Interplanetary Turbulence
AU - Bernard J. Vasquez
AU - Charles W. Smith
AU - Roy B. Torbert
PY - 2026
DA - 2026/10/13
JO - The Astrophysical Journal Supplement Series
DO - 10.3847/1538-4365/aeaa3d
UR - https://iopscience.iop.org/article/10.3847/1538-4365/aeaa3d
AB - The distribution of energy within interplanetary turbulence has been modeled with a slab part with wavevectors along the background magnetic field B ₀ and a 2D part with wavevectors perpendicular to B ₀ . J. W. Bieber et al. (1996) ascertained the amount of magnetic energy in the slabs relative to the total perpendicular magnetic energy observed by determining the ratio of the spectral amplitude squared values that characterize the spectra of the fluctuating magnetic field components that are perpendicular to B ₀ and each other. Integrals over the spectrum of the slab and 2D model were made to establish how the spectrum would appear to a spacecraft. In the present analysis, certain factors that belong to the solution of the integrals are not in the formulas published in J. W. Bieber et al. (1996). The missing factors are provided here. A generalization is made to account for energy in all directions for both slab and 2D turbulence, separately, and for a parallel magnetic field component associated with the 2D turbulence. With this generalization, the fraction of energy in slabs is reduced by 30%–40% in relative change, which makes the 2D turbulence generally more significant in the dissipation range. For individual intervals, the accuracy of the energy fraction can be enhanced by limiting observations to a particular range of angles between the sampling direction and B ₀ . A method to obtain accurate spectra fit parameters is demonstrated with an example.
SN - 0067-0049
SN - 1538-4365
ER -