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arXiv 2102.02305astro-ph.SR
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用帕克太阳探测器观测的太阳黑子数和太阳耀斑、日冕物质抛射和太阳风之字形事件的等待时间分布的相关性

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

Markus J. Aschwanden, Thierry Dudok de Wit

摘要:

在4个太阳活动周(1974-2012年)的年观测数据中,太阳耀斑和{ \sl日冕物质抛射(CME)}的等待时间分布呈现幂律分布函数,斜率在$α_τ \approx 1.4-3.2$范围内。我们发现等待时间幂律斜率$α_τ$和{ \sl太阳黑子数(SN)}之间有密切的相关性,即,$α_τ$ = 1.38 + 0.01 $\times$ SN。等待时间分布可以用$N(τ) = N_0$ $(τ_0 + τ)^{-α_τ}$形式的帕累托型函数拟合,其中偏移$τ_0$取决于仪器灵敏度、事件的检测阈值和脉冲堆积效应。等待时间分布的时变幂律斜率$α_τ(t)$仅取决于太阳总磁通量(由太阳黑子数量化)或耀斑速率,与{ \sl自组织临界(SOC)}或{ \sl磁流体动力学(MHD)}湍流模型的其他物理参数无关。在太阳风之字形事件中也发现了$α_τ\approx 1.2-1.6$的幂律斜率,正如{ \sl Parker Solar Probe(PSP)}所观察到的那样。我们的结论是,在日光层太阳风之字形事件的年度变化调制耀斑和日冕物质抛射率起源于光球和低日冕。

英文摘要:

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.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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