论文标题
间歇性的统计分析及其与近日环境中质子加热的关联
Statistical analysis of intermittency and its association with proton heating in the near Sun environment
论文作者
论文摘要
我们使用Parker太阳能探针前六个相遇中的数据,并采用增量的部分差异($ PVI $)方法来研究内部地球内相干结构的统计特性,目的是探索磁场间歇性和可观察到的磁场之间的物理连接,例如等化后的降温和驱动驱动和湍流。我们的结果支持质子加热位于附近的质子加热,并与以$ pvi \ geq 1 $为特征的磁性结构密切相关。我们表明,这种事件平均构成数据集的$ \ 19 \%$,尽管可能会根据等离子体参数而发生变化。我们表明,在较低的$ wts $下进行幂律缩放后,所有六个相遇的等待时间分布($ wt $)在所有六个遭遇中都是一致的。该结果表明连贯的结构在太阳风中均匀分布,而是倾向于紧密相关并形成簇。我们观察到,通常与重新连接排气相关的最强磁性不连续性,$ PVI \ geq 6 $是磁性能量在质子加热中局部消散的地点,并且与质子温度突然变化有关。但是,由于此类事件的稀缺性,它们对能量耗散的相对贡献很小。考虑到聚类效应,我们表明,较小的规模,更频繁的结构,PVI之间,$ 1 \ Lessim Pvi \ Lessim 6 $,在磁能消散中起主要作用。此类事件的数量密度与全局太阳风温度密切相关,较密度的间隔与较高的$ t_ {p} $相关。
We use data from the first six encounters of Parker Solar Probe and employ the Partial Variance of Increments ($PVI$) method to study the statistical properties of coherent structures in the inner heliosphere with the aim of exploring physical connections between magnetic field intermittency and observable consequences such as plasma heating and turbulence dissipation. Our results support proton heating localized in the vicinity of, and strongly correlated with, magnetic structures characterized by $PVI \geq 1$. We show that on average, such events constitute $\approx 19\%$ of the dataset, though variations may occur depending on the plasma parameters. We show that the waiting time distribution ($WT$) of identified events is consistent across all six encounters following a power-law scaling at lower $WTs$. This result indicates that coherent structures are not evenly distributed in the solar wind but rather tend to be tightly correlated and form clusters. We observe that the strongest magnetic discontinuities, $PVI \geq 6$, usually associated with reconnection exhausts, are sites where magnetic energy is locally dissipated in proton heating and are associated with the most abrupt changes in proton temperature. However, due to the scarcity of such events, their relative contribution to energy dissipation is minor. Taking clustering effects into consideration, we show that smaller scale, more frequent structures with PVI between, $1\lesssim PVI \lesssim 6$, play the major role in magnetic energy dissipation. The number density of such events is strongly associated with the global solar wind temperature, with denser intervals being associated with higher $T_{p}$.