发表机构
University of Arizona; University College London; University of California, Berkeley; Smithsonian Astrophysical Observatory（亚利桑那大学; 伦敦大学学院; 加州大学伯克利分校; 史密森尼天体物理台）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究利用帕克太阳探测器实测速度分布，对比双麦克斯韦模型，发现简化模型高估近太阳太阳风中质子回旋波阻尼并低估波发射。
AI 中文摘要
对远离局部热力学平衡的弱碰撞日球层等离子体中能量输运和耗散的定量描述是一个突出的科学问题。一个核心挑战在于确定非麦克斯韦速度空间结构如何影响相干离子尺度波的阻尼和发射，尤其是与背景等离子体速度分布的简化解析模型相比。在本工作中，我们研究了平行传播的质子回旋波的阻尼和发射，采用了帕克太阳探测器上SPAN-I仪器在日心距离30.1太阳半径处太阳风中左旋极化波的持续风暴期间测量的两种质子速度分布模型。使用实测速度分布而非双分量双麦克斯韦模型，预测的不稳定性与观测到的相干波一致。在两种模型均预测净阻尼的时间区间内，实测速度分布函数模型在90%的情况下给出较弱的阻尼，其积分加热率相对于双麦克斯韦模型降低了0.44。这些结果表明，简化的解析速度分布模型可能高估了近太阳太阳风中的回旋阻尼，并低估了波发射。
英文摘要
Quantification of energy transport and dissipation in weakly collisional heliospheric plasmas that are far from local thermodynamic equilibrium is an outstanding scientific problem. A central challenge is determining how non-Maxwellian velocity-space structure affects damping and emission of coherent ion-scale waves, especially compared to simplified analytical models for background plasma velocity distributions. In this work, we study the damping and emission of parallel-propagating proton cyclotron waves for two models of proton velocity distributions measured by the SPAN-I instrument on board Parker Solar Probe during an extended storm of waves with left-hand polarization in the solar wind at a heliocentric distance of 30.1 solar radii. Using the measured velocity distribution rather than a two-component bi-Maxwellian model predicts instabilities consistent with the observed coherent waves. For intervals in which both models predict net damping, the observed VDF model yields weaker damping in 90\% of cases, with a reduction in the integrated heating rate of 0.44 relative to the bi-Maxwellian model. These results suggest that simplified analytical velocity distribution models may overestimate cyclotron damping and underestimate wave emission in the near-Sun solar wind.
Comments20 pages, 10 figures, under review at Solar Physics
