发表机构
School of Computing and Artificial Intelligence, Southwest Jiaotong University; School of Physical Science and Technology, Southwest Jiaotong University; Department of Applied Sciences, Khalsa College of Engineering and Technology（西南交通大学计算机与人工智能学院; 西南交通大学物理科学与技术学院; 卡尔萨工程与技术学院应用科学系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究针对脉冲星风电流片中的类离子声模式，提出压力平衡存在判据，指出该模式仅存在于特定参数区域，为波驱动的局域耗散研究奠定基础。
AI 中文摘要
脉冲星风的电子-正电子等离子体缺乏常规类离子声压缩模式所需的惯性重粒子种类。然而，如果离子混入重联的条纹风电流片中，则可能出现低频压缩分支。我们针对离子负载、压力平衡的脉冲星风电流片中的此类类离子声模式，发展了一种局部共动系理论。背景模型通过光柱磁场和戈德赖希-朱利安密度直接与脉冲星可观测物理量相联系，而电流片结构则由类哈里斯的磁场反转和依赖粒子种类的压缩因子表示。对等离子体对（电子-正电子）处理为无惯性的热力学屏蔽群体，而离子则描述为温热的、非相对论的、磁化流体。压力平衡固定了等离子体对和离子的温度，而非自由指定。这给出了以脉冲星自转参数表示的、经等离子体对屏蔽的离子声速的闭合表达式。我们推导了温热离子的静电色散关系，并讨论了此类电流片中类离子声分支能够存在的条件。我们发现，类离子声模式并非对所有电流片参数都出现，而是局限于参数空间的特定区域。因此，仅离子负载不足以维持该模式；局部电流片条件决定了可容许的类离子声模式存在于何处。由此，任何由该模式介导的波驱动反常耗散或粒子加热必然高度局域化，而非均匀分布于条纹风各处。该框架给出了模式可存在的物理区域，为未来动力学激发与阻尼研究提供了必要基础。
英文摘要
Pulsar wind electron--positron plasma lacks the heavy inertial species required for the conventional ion-acoustic-like compressive modes. However, if ions are mixed into the reconnecting striped-wind current sheet, a low-frequency compressive branch can appear. We develop a local, comoving-frame theory for such ion-acoustic-like modes in an ion-loaded, pressure-balanced pulsar-wind current sheet. The background model connects directly to pulsar observables through the light-cylinder magnetic field and Goldreich--Julian density, while the sheet structure is represented by a Harris-like field reversal and species-dependent compression factors. The pair species are treated as inertialess thermodynamic shielding populations, whereas the ions are described by a warm, nonrelativistic, magnetized fluid. Pressure balance fixes the pair and ion temperatures rather than prescribing them freely. This gives a closed expression for the pair-shielded ion-acoustic speed in terms of pulsar spin parameters. We derive the warm-ion electrostatic dispersion relation and discuss the conditions under which the ion-acoustic-like branch can exist in such a current sheet. We find that the ion-acoustic-like mode does not occur for all sheet parameters but is restricted to specific regions of parameter space. Thus, ion loading alone is not sufficient to sustain the mode; the local current-sheet conditions determine where an admissible ion-acoustic-like mode can exist. Consequently, any wave-driven anomalous dissipation or particle heating mediated by this mode must be highly localized rather than distributed uniformly across the striped wind. This framework provide the physical domain where the mode can exist, providing the necessary foundation for future studies of kinetic excitation and damping.
Comments20 pages, 5 figures
