Latitudinal cosmic ray gradients: Their relation to solar activity asymmetry
Latitudinal cosmic ray gradients: Their relation to solar activity asymmetry
复制标题
纬向宇宙射线梯度：它们与太阳活动不对称性的关系
DOI：
10.1029/90ja02502
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发表时间：
1991
期刊：
影响因子：
--
通讯作者：
D. Smart
中科院分区：
文献类型：
--
作者：
D. B. Swinson;J. Humble;M. Shea;D. Smart
本文分析了1965年至1985年间北方和南方半球地下宇宙线望远镜观测到的行星际磁场（IMF）的长期变化，以研究纬向宇宙线梯度N{sub p}的长期性质。这种梯度的性质是从纬度梯度和IMF B之间的相互作用所产生的太阳周日宇宙线各向异性的B {times} {gradient} N{sub p}贡献推断出来的。在早先的一篇论文中，作者指出了同一时期太阳活动的纬度梯度特征与南北不对称性之间的对应关系，并试图用两种梯度的组合来解释这一结果：南北对称梯度和南北不对称梯度。在本文中，作者提出的结果表明，在太阳活动的不对称性取代日光层中性片无论是低于或高于地球（平均），根据太阳活动的不对称性的方向。这种位移，加上相对于中性片对称的纬向宇宙线密度梯度，产生了从地球上看不对称的纬向宇宙线梯度。宇宙射线数据与对称的（相对于中性片）纬向宇宙射线密度梯度一致，其中密度最初随着与中性片的距离而减小，然后随着与中性片的距离增加而再次增加。来自倾斜地下宇宙射线望远镜的额外数据，从北纬60度到南纬50度观察，提供了远离中性片的纬度梯度的信息。«少
Data obtained by underground cosmic ray telescopes in the northern and southern hemispheres between 1965 and 1985 are analyzed as a function of the interplanetary magnetic field (IMF) sense to examine the long-term nature of the latitudinal cosmic ray gradient, {gradient}N{sub p}. The nature of this gradient is inferred from the B {times} {gradient} N{sub p} contribution to the solar diurnal cosmic ray anisotropy arising from the interaction between the latitudinal gradient and the IMF B. In an earlier paper, the authors noted a correspondence between the characteristics of the latitudinal gradient and the north-south asymmetry in activity on the Sun during the same period and attempted to explain the result in terms of a combination of two gradients: a north-south symmetrical gradient and a north-south asymmetrical gradient. In this paper, the authors present results showing that asymmetry in activity on the Sun displaces the heliospheric neutral sheet either below or above the Earth (on average), according to the direction of the solar activity asymmetry. This displacement, combined with a latitudinal cosmic ray density gradient that is symmetrical in relation to the neutral sheet, produces a latitudinal cosmic ray gradient that is asymmetrical when viewed from the Earth. The cosmicmore » ray data are consistent with a symmetric (in relation to the neutral sheet) latitudinal cosmic ray density gradient in which the density initially decreases with distance from the neutral sheet and then increases again with increasing distance from the sheet. Additional data from inclined underground cosmic ray telescopes, viewing from 60{degree}N to 50{degree}S, give information on latitudinal gradients further from the neutral sheet.« less