A fourth-order accurate continuum kinetic Vlasov solver and a systematic method for constructing customizable kinetic equilibria are demonstrated to be powerful tools for the study of nonuniform collisionless low-beta plasmas. The noise-free methodology is applied to investigate two gradient-driven instabilities in 4D $(x,y,v_x,v_y)$ phase space: the Kelvin–Helmholtz instability and the lower hybrid drift instability. Nonuniform two-species configurations where ion gyroradii are comparable to gradient scale lengths are explored. The approach sheds light on the evolution of the pressure tensor in Kelvin–Helmholtz instabilities and demonstrates that the associated stress tensor deviates significantly from the gyroviscous stress tensor. Even at high magnetization, first-order approximations to finite-gyromotion physics are shown to be inadequate for the Kelvin–Helmholtz instability, as shear scales evolve to become on par with gyromotion scales. The methodology facilitates exploring transport and energy partitioning properties associated with lower hybrid drift instabilities in low-beta plasma configurations. Distribution function features are captured in detail, including the formation of local extrema in the vicinity of particle-wave resonances. The approach enables detailed targeted investigations and advances kinetic simulation capability for plasmas in which gyromotion plays an important role.

中文翻译：

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非均匀低β等离子体中不稳定性和陀螺运动物理的高保真动力学建模

四阶精确连续动力学 Vlasov 求解器和构建可定制动力学平衡的系统方法被证明是研究非均匀无碰撞低 β 等离子体的有力工具。无噪声方法用于研究 4D 中两个梯度驱动的不稳定性$(X,是,v_X,v_{是})$相空间：开尔文-亥姆霍兹不稳定性和较低的混合漂移不稳定性。探索了离子陀螺半径与梯度尺度长度相当的非均匀两种配置。该方法揭示了开尔文-亥姆霍兹不稳定性中压力张量的演变，并证明相关的应力张量显着偏离陀螺粘性应力张量。即使在高磁化强度下，有限陀螺运动物理的一阶近似也被证明对于开尔文-亥姆霍兹不稳定性是不够的，因为剪切尺度演变为与陀螺运动尺度相当。该方法有助于探索与低β等离子体配置中较低的混合漂移不稳定性相关的传输和能量分配特性。详细捕获分布函数特征，包括在粒子波共振附近形成局部极值。该方法可以进行详细的有针对性的研究，并提高对回转运动起重要作用的等离子体的动力学模拟能力。