One of the grand challenge problems of the giant planet magnetospheres is the issue of nonadiabatic plasma heating. Simple turbulent heating models consider the energy cascade rate from one scale to another where the energy density is based on perpendicular magnetic fluctuations of counterpropagating Alfvén waves. Analytical expressions from turbulence theory for the heating rate density have yielded promising results for the observed ion heating at Jupiter and Saturn. Here, we compare ion heating using hybrid simulations of the Kelvin–Helmholtz instability and analytical estimates in an effort to validate turbulence theory and further understand the nature of the ion heating. Heating rate densities ∼10⁻¹⁵ W/m³ are produced in our three‐dimensional Kelvin–Helmholtz simulations during the nonlinear growth phase and compare favorably with analytical estimates. Results targeting Saturn will be discussed in the broader context of radial plasma transport in the rapidly rotating magnetospheres.

中文翻译：

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土星的磁层顶边界处的开尔文-亥姆霍兹相关湍流加热

巨大的行星磁层面临的巨大挑战之一是非绝热等离子体加热问题。简单的湍流加热模型考虑了从一个尺度到另一个尺度的能量级联速率，其中能量密度基于反向传播的Alfvén波的垂直磁涨落。来自湍流理论的加热速率密度的解析表达式为在木星和土星上观测到的离子加热产生了可喜的结果。在这里，我们使用开尔文-亥姆霍兹不稳定性的混合模拟和分析估计来比较离子加热，以验证湍流理论并进一步了解离子加热的性质。加热速率密度〜10 ^-15  W / m ³在我们的三维Kelvin-Helmholtz模拟中，在非线性增长阶段生成了这些结果，并且与分析估计值相比具有优势。针对土星的结果将在快速旋转的磁层中径向等离子体传输的更广泛背景下进行讨论。