当前位置: X-MOL 学术Sol. Phys. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Scaling Features of Diurnal Variation of Galactic Cosmic Rays
Solar Physics ( IF 2.8 ) Pub Date : 2021-08-18 , DOI: 10.1007/s11207-021-01866-6
Renata Modzelewska 1 , Agnieszka Gil 1, 2 , Agata Krasińska 2 , Anna Wawrzaszek 2
Affiliation  

We analyze the scaling properties of the diurnal variation of galactic cosmic rays (GCRs) in Solar Cycle 24 and the solar minima between Solar Cycles 23/24 and 24/25 for 2007 – 2019 based on the count rates of the Oulu, Newark, Hermanus, and Potchefstroom neutron monitors. The scaling features of the GCR diurnal variation are studied by evaluating the Hurst exponent, a quantitative parameter used as an indicator of the state of the randomness of a time series. We estimate the Hurst exponents for GCR diurnal-variation parameters amplitude and phase using structure-function and detrended-fluctuation-analysis methods. Results show that the Hurst exponents for the GCR diurnal variation vary in the range from \(\approx0.3\) to \(\approx0.9\), with a general tendency of being systematically above 0.5. It suggests that the GCR diurnal variation reveals a more persistent structure than Brownian motion. However, the time series of GCR diurnal-variation amplitude and phase evolve from a more persistent structure in the solar minimum between Solar Cycles 23/24 in 2007 – 2009 to a more random character in and near the solar maximum 2012 – 2014. This observation seems to be in agreement with the general configuration of the heliosphere through the 11-year solar-activity cycle. Moreover, the temporal profile of the Hurst exponent for GCR diurnal amplitude and phase around the beginning of the solar minimum between Solar Cycles 24/25 (2018 – 2019) differs from the solar minimum between Solar Cycles 23/24 in 2007 – 2009, suggesting a dependence on solar-magnetic polarity. These findings could shed more light on GCR particle transport in the turbulent heliosphere over the solar cycle.



中文翻译:

银河宇宙线日变化的标度特征

我们根据奥卢、纽瓦克、赫曼努斯的计数率,分析了 2007 年至 2019 年第 24 轮太阳周期中银河宇宙射线 (GCR) 的日变化以及 23/24 和 24/25 太阳周期之间的太阳极小值的标度特性和 Potchefstroom 中子监视器。GCR 日变化的尺度特征是通过评估 Hurst 指数来研究的,Hurst 指数是一个定量参数,用作时间序列随机性状态的指标。我们使用结构函数和去趋势波动分析方法估计 GCR 日变化参数幅度和相位的 Hurst 指数。结果表明,GCR 日变化的 Hurst 指数在\(\approx0.3\)\(\approx0.9\)的范围内变化,总体趋势是系统地高于 0.5。这表明 GCR 日变化显示出比布朗运动更持久的结构。然而,GCR 日变化幅度和相位的时间序列从 2007 年至 2009 年第 23/24 次太阳活动周期之间的太阳活动极小期更持久的结构演变为 2012 至 2014 年太阳活动极大期及其附近的更随机特征。似乎与通过 11 年太阳活动周期的日光层的一般配置一致。此外,在太阳活动周期 24/25(2018-2019)之间的太阳活动极小期开始附近的 GCR 日振幅和相位的赫斯特指数的时间分布不同于 2007-2009 年太阳活动周期 23/24 之间的太阳活动极小期,这表明对太阳磁极性的依赖。

更新日期:2021-08-19
down
wechat
bug