基于经验模式分解的太阳南北半球黑子面积的Rieger-type周期相位分析
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摘要
采用经验模式分解技术研究了从第12到第24太阳活动周黑子面积数据中的Rieger-type周期,以及它们在南北半球上的相位关系。研究发现:(1)Rieger-type周期尺度以及时间尺度在两个半球上是不一样的,从而导致了半球分布的不对称性;(2)平均Rieger-type周期在北半球上的周期长度略大于南半球上的;(3)占主导地位半球的Rieger-type周期的相位不一定是超前的,半球Rieger-type周期尺度相近的也并不一定是相关性强的。
Empirical mode decomposition(EMD) technique is used to study the Rieger-type cycle in the sunspot area data from the 12 th to 24 th solar cycles and their phase relations in the northern and southern hemispheres. It is found that:(1) the Rieger-type cycle scale and the time scale are different in the two hemispheres, which leads to the asymmetry of the hemispheric distribution;(2) the average Rieger-type cycle length in the northern hemisphere is slightly longer than that in the southern hemisphere;(3) the phase of the dominant hemisphere is not necessarily ahead of time. The hemispherical Rieger-type with similar cycle scales is not necessarily a strong correlation.
Empirical mode decomposition(EMD) technique is used to study the Rieger-type cycle in the sunspot area data from the 12 th to 24 th solar cycles and their phase relations in the northern and southern hemispheres. It is found that:(1) the Rieger-type cycle scale and the time scale are different in the two hemispheres, which leads to the asymmetry of the hemispheric distribution;(2) the average Rieger-type cycle length in the northern hemisphere is slightly longer than that in the southern hemisphere;(3) the phase of the dominant hemisphere is not necessarily ahead of time. The hemispherical Rieger-type with similar cycle scales is not necessarily a strong correlation.
引文
[1] GURGENASHVILI E, ZAQARASHVILI T V, KUKHIANIDZE V, et al. Rieger-type periodicity during solar cycles 14-24: estimation of dynamo magnetic field strength in the solar interior[J]. The Astrophysical Journal, 2016, 826(1): article id. 55(10pp).
[2] ZAQARASHVILI T V, CARBONELL M, OLIVER R, et al. Quasi-biennial oscillations in the solar tachocline caused by magnetic Rossby wave instabilities[J]. The Astrophysical Journal Letters, 2010, 724(1): L95-L98.
[3] LI K J, FENG W, XU J C, et al. Why is the solar constant not a constant? [J]. The Astrophysical Journal, 2012, 747(2): article id. 135(5pp).
[4] LI K J, SHI X J, FENG W, et al. Long-term variations of the coronal rotation and solar activity[J]. Monthly Notices of the Royal Astronomical Society, 2012, 423(4): 3584-3588.
[5] VERMA V K, JOSHI G C, PALIWAL D C. Study of periodicities of solar nuclear gamma ray flares and sunspots[J]. Solar Physics, 1992, 138(1): 205-208.
[6] 陆阳平, 乐贵明, 赵浩峰, 等. 21～24太阳活动周首个高纬黑子和首个X级耀斑的半球特点与太阳活动的南北不对称性的关系[J]. 天文研究与技术, 2016, 13(2): 150-152.
[7] GURGENASHVILI E, ZAQARASHVILI T V, KUKHIANIDZE V, et al. North-south asymmetry in Rieger-type periodicity during solar cycles 19-23[J]. The Astrophysical Journal, 2017, 845(2): article id. 137(11pp).
[8] HUANG N E, SHEN Z, LONG S R, et al. The empirical mode decomposition and the Hilbert spectrum for nonlinear and non-stationary time series analysis[C]// Proceedings of the Mathematical, Physical and Engineering Sciences. 1971: 903-995.
[9] 冯雯, 谢婧岚, 李可军. 黑子面积随黑子数变化的统计研究[J]. 天文研究与技术, 2016, 13(2): 153-159.
[2] ZAQARASHVILI T V, CARBONELL M, OLIVER R, et al. Quasi-biennial oscillations in the solar tachocline caused by magnetic Rossby wave instabilities[J]. The Astrophysical Journal Letters, 2010, 724(1): L95-L98.
[3] LI K J, FENG W, XU J C, et al. Why is the solar constant not a constant? [J]. The Astrophysical Journal, 2012, 747(2): article id. 135(5pp).
[4] LI K J, SHI X J, FENG W, et al. Long-term variations of the coronal rotation and solar activity[J]. Monthly Notices of the Royal Astronomical Society, 2012, 423(4): 3584-3588.
[5] VERMA V K, JOSHI G C, PALIWAL D C. Study of periodicities of solar nuclear gamma ray flares and sunspots[J]. Solar Physics, 1992, 138(1): 205-208.
[6] 陆阳平, 乐贵明, 赵浩峰, 等. 21～24太阳活动周首个高纬黑子和首个X级耀斑的半球特点与太阳活动的南北不对称性的关系[J]. 天文研究与技术, 2016, 13(2): 150-152.
[7] GURGENASHVILI E, ZAQARASHVILI T V, KUKHIANIDZE V, et al. North-south asymmetry in Rieger-type periodicity during solar cycles 19-23[J]. The Astrophysical Journal, 2017, 845(2): article id. 137(11pp).
[8] HUANG N E, SHEN Z, LONG S R, et al. The empirical mode decomposition and the Hilbert spectrum for nonlinear and non-stationary time series analysis[C]// Proceedings of the Mathematical, Physical and Engineering Sciences. 1971: 903-995.
[9] 冯雯, 谢婧岚, 李可军. 黑子面积随黑子数变化的统计研究[J]. 天文研究与技术, 2016, 13(2): 153-159.