Correlation of the sunspot number and the waiting time distribution of solar flares, coronal mass ejections, and solar wind switchback events observed with the Parker Solar Probe
Waiting time distributions of solar flares and {\sl coronal mass ejections (CMEs)} exhibit power law-like distribution functions with slopes in the range of $α_τ \approx 1.4-3.2$, as observed in annual data sets during 4 solar cycles (1974-2012). We find a close correlation between the waiting time power law slope $α_τ$ and the {\sl sunspot number (SN)}, i.e., $α_τ$ = 1.38 + 0.01 $\times$ SN. The waiting time distribution can be fitted with a Pareto-type function of the form $N(τ) = N_0$ $(τ_0 + τ)^{-α_τ}$, where the offset $τ_0$ depends on the instrumental sensitivity, the detection threshold of events, and pulse pile-up effects. The time-dependent power law slope $α_τ(t)$ of waiting time distributions depends only on the global solar magnetic flux (quantified by the sunspot number) or flaring rate, independent of other physical parameters of {\sl self-organized criticality (SOC)} or {\sl magneto-hydrodynamic (MHD)} turbulence models. Power law slopes of $α_τ\approx 1.2-1.6$ were also found in solar wind switchback events, as observed with the {\sl Parker Solar Probe (PSP)}. We conclude that the annual variability of switchback events in the heliospheric solar wind is modulated by flare and CME rates originating in the photosphere and lower corona.
Analysis of the distribution, rotation and scale characteristics of solar wind switchbacks: comparison between the first and second encounters of Parker Solar Probe
Turbulence characteristics of switchbacks and non-switchbacks intervals observed by \emph{Parker Solar Probe}
我们使用\emph{Parker Solar Probe}(\emph{PSP})的现场测量,以分析太阳风湍流的特征,在第一次太阳相遇期间覆盖径向距离之间的$35.7R_\odot$和$41.7R_\odot$。在我们的分析中,我们将所谓的之字形(SB)间隔(折叠磁场线)与非之字形(NSB)间隔(主要遵循帕克螺旋场)隔离开来。使用一种基于条件关联函数的技术,我们分别在SB和NSB间隔中估计了Elsasser、磁场和体速度场的功率谱。通过对两种间隔的湍流能谱的比较,我们发现了以下特点:1)后向传播Elsasser场$z^-$的去相关长度在NSB间隔中比在SB间隔中大;(2)SB层段的磁功率谱比NSB层段陡,谱指数接近-5/3,其具有接近-3/2的光谱指数; 3)SB和NSB湍流都是不平衡的,NSB具有最大的交叉螺旋度,4)SB间隔中的剩余能量大于NSB,以及5)所分析的波动由在\emph{sunward}中传播的Alfvénic波动主导(\emph{anti-sunward})方向,用于SB(NSB)湍流。这些观察到的特征提供了进一步的证据,证明\emph{PSP}观察到的之字形与折叠磁场线有关,从而深入了解其湍流性质。
Possible Evolution of Minifilament-Eruption-Produced Solar Coronal Jets, Jetlets, and Spicules, into Magnetic-Twist-Wave "Switchbacks" Observed by the Parker Solar Probe (PSP)
Direct Evidence of Non-Ideal Dissipative Dynamics in Solar Wind Magnetic Switchbacks
Space Sciences Laboratory, University of California, Berkeley(加州大学伯克利分校空间科学实验室);Physics Department, University of California, Berkeley(加州大学伯克利分校物理系);Physics Department, University of Alberta(阿尔伯塔大学物理系)
Generation and Expansion-Driven Growth of Switchbacks in the Outer Solar Corona and Solar Wind
Imperial College London(帝国理工学院);University of California, Los Angeles(加州大学洛杉矶分校);Auburn University(奥本大学);Space Sciences Laboratory, University of California, Berkeley(加州大学伯克利分校空间科学实验室);Istituto per la Scienza e Tecnologia dei Plasmi (ISTP), Consiglio Nazionale delle Ricerche(等离子体科学与技术研究所,意大利国家研究委员会);The University of Texas at Austin(德克萨斯大学奥斯汀分校)
Near-Sun Switchbacks Show Statistical Signatures of Solar Activity
Inter-University Centre for Astronomy and Astrophysics(大学间天文与天体物理中心);International Space Science Institute(国际空间科学研究所);LPC2E, OSUC, Univ Orleans, CNRS, CNES(地球与行星物理学实验室,观测宇宙学与气候环境统一研究组织,奥尔良大学,法国国家科学研究中心,法国国家太空研究中心);SETI Institute(搜寻地外文明研究所);Lockheed Martin Solar and Astrophysics Laboratory(洛克希德·马丁太阳与天体物理实验室)
Features of magnetic field switchbacks in relation to the local-field geometry of large-amplitude Alfvénic oscillations: \emph{Wind} and \emph{PSP} observations
Properties of Magnetic Switchbacks in the Near-Sun Solar Wind
Center for Astrophysics, Harvard & Smithsonian(哈佛-史密森天体物理中心);Institut de Recherche en Astrophysique et Planétologie, CNES, CNRS, Université de Toulouse(天体物理学与行星学研究所,法国国家空间研究中心,法国国家科学研究中心,图卢兹大学);Department of Physics, Imperial College London(帝国理工学院物理系);Space Sciences Laboratory, University of California, Berkeley(加州大学伯克利分校空间科学实验室);Astronomy and Space Physics Department, National Taras Shevchenko University of Kyiv(基辅塔拉斯舍甫琴科国立大学天文与空间物理系);Department of Climate and Space Sciences and Engineering, University of Michigan(密歇根大学气候与空间科学与工程系);LPC2E, OSUC, Univ Orleans, CNRS, CNES(奥尔良大学地球与环境过程实验室,观测与研究宇宙学与气候系统观测站,法国国家科学研究中心,法国国家空间研究中心);International Space Science Institute(国际空间科学研究所)
Potential Solar Precursors to Magnetic Switchbacks
Inter-University Centre for Astronomy and Astrophysics(大学间天体物理中心);Max Planck Institute for Solar System Research(马克斯·普朗克太阳系统研究所);Korea Astronomy and Space Science Institute(韩国天文与空间科学研究院);Space Research and Technology Institute, Bulgarian Academy of Sciences(保加利亚科学院空间技术与研究所);Heliophysics Science Division, NASA Goddard Space Flight Center(NASA戈达德太空飞行中心日球物理科学部);Earth, Planetary and Space Sciences, University of California, Los Angeles(加州大学洛杉矶分校地球、行星与空间科学系);LPC2E, OSUC, Univ Orleans, CNRS, CNES(奥尔良大学、国家科学研究中心、国家空间研究中心 LPC2E 实验室);Sorbonne Université, École polytechnique, Institut Polytechnique de Paris, Université Paris Saclay, Observatoire de Paris-PSL, CNRS, Laboratoire de Physique des Plasmas (LPP)(索邦大学、巴黎综合理工学院、巴黎理工学院、巴黎萨克雷大学、巴黎天文台-PSL、CNRS、等离子体物理实验室(LPP));University of Ioannina(约阿尼纳大学);Johns Hopkins Applied Physics Laboratory(约翰斯·霍普金斯大学应用物理实验室)
Coherent events at ion scales in the inner Heliosphere: \textit{Parker Solar Probe} observations during the first Encounter
\textit{Parker Solar Probe}在其第一个近日点嵌入一个高度阿尔夫文慢流时,已经显示出普遍存在的强磁场偏转,即之字形。在这里,我们研究的湍流磁场波动的离子尺度在三个间隔,其特征在于一个不同的之字形活动,确定的行为的磁场径向分量,$B_r$。\textit{Quiet}($B_r$未显示出显著波动)、\textit{weak}($B_r$具有强波动但无反转)和\textit{strong}($B_r$具有完全反转)周期也显示出离子量和Alfvénicity的不同行为。然而,光谱分析表明,每个流的特征在于由典型的Kolmogorov/Kraichnan幂律在惯性范围内,其次是周围的特征离子尺度的休息。该频率范围的特征在于强间歇性活动,存在非压缩相干结构,例如电流片和涡旋状结构,以及被识别为离子回旋模式的波包。虽然,所有这些间歇性事件已被检测到的三个时期,他们有不同的影响,在他们每个人。电流片在\textit{strong}周期中占主导地位,波包在\textit{quiet}间隔中最常见;而在\textit{weak}周期中,观察到涡旋和波包的混合物。这项工作提供了一个深入了解加热问题的碰撞无等离子体,适合在新的太阳能任务的背景下,特别是\textit{Solar Orbiter},这将允许一个准确的磁连通性分析,链接到源区域的不同的间歇性事件的存在。
Averaging Effects on the Solar Wind Alfven Mach Number: Implications for Switchbacks and Alfven Transition
University of Delaware(特拉华大学);Princeton University(普林斯顿大学);University of California, Berkeley(加州大学伯克利分校);Mahidol University(玛希隆大学);University of Orléans(奥尔良大学);Kasetsart University(泰国农业大学);NASA Goddard Space Flight Center(美国宇航局戈达德太空飞行中心)