排序方式: 共有42条查询结果,搜索用时 468 毫秒
21.
22.
23.
In this paper Pi2 pulsations at Zhongshan Station of Antarctica are analyzed from October 1 - 31, 1996. Their characteristics e. g. occurrence frequency,frequency, and polarization are studied. The characteristics of Pi2 pulsations are summerized as follows: (1 ) Pi2 pulsations at Zhongshan Station usually take place from 2000 MLT to 0200 MLT; the main frequencies are between 6. 79 mHz and 13. 58mHZ; (2 ) Pi2 pulsations with low frequencies are dominent. The range of main frequencies becomes narrow at midnight; (3) The Polarization of Pi2 pulsations are almost linear; (4) About the orientation of major axes the NW-SE direction is dominent before 2200 MLT and NE-SW is dominent after 2200 MLT. The generation mechanism of Pi2 pulsations at Zhongshan Station is discussed theoretically. 相似文献
24.
25.
26.
Digital filter technology isan importantmethod in study of geomagnetic pul- sations in Antarctica.The signals received by pulsation magnetometer on the ground include varioustypesofmagnetic pulsations.Some types of pulsations or some frequen- cy bands of pulsations can be extracted from the signals by means of digital filter tech- nology because types of pulsations are defined according to their frequency range.In this paper usual digital filter technology is provided for study of magnetic pulsations in Antarctica and some examples are introduced. 相似文献
27.
1 IntroductionThepolarregionisanimportantareaforenergeticcouplingbetweensolarwindandearth’smagnetosphere .Thecuspisthedirectpathforsolarwindpenetratingintothemagnetosphereorevenintotheionosphereanditalsoisaconvergentregionforalotofmagnetosphericbounda… 相似文献
28.
Two induction magnetometers have been installed at Chinese Zhongshan Station and Australia Davis Station, Antarctica respectively. We adopt the cross spectral analysis technique to analyze the data of the two induction magnetometers, in June, September, December 1996 and March 1997, and to investigate Pc5 frequency range pulsation (150 600 s) occurrence and propagation in cusp latitude. The results are summarized as follows: At Zhongshan Davis Station, the magnetic pulsations in Pc5 frequency band can occurs over a wide time, but more frequently at pre local magnetic noon and pre local magnetic midnight. The Pc5 pulsations have no significant seasonal variation in the amplitude, occurrence and propagation. The amplitude has a small peak at pre local magnetic noon and large value sometimes at pre local magnetic midnight. In daytime, the Pc5 pulsations propagate westward in morning and eastward in afternoon, and reversal at local magnetic noon. In nighttime, the Pc5 pulsations propagate westward before 20:00 MLT and eastward after 20:00 MLT. Near dusk time, the Pc5 pulsations propagate irregularly. These characteristics indicate that the Pc5 pulsations have different source at different local magnetic time. 相似文献
29.
本文重点分析了在1989年3月13日发生的强急始型磁暴期间观测到的丰富的地磁脉动现象.文中列出各种地磁脉动发生的时间和波形曲线范例,并对各种地磁脉动做了傅里叶谱分析.这不仅可以帮助我们了解这些地磁脉动和磁暴的关系,而且能使我们进一步认识磁暴过程的能量传输实质. 相似文献
30.
Pi2地磁脉动的理论进展 总被引:1,自引:1,他引:1
目前,国内外在Pi2脉动的理论研究上取得了很大进展,现在问题的焦点是如何完整地解释Pi2脉动的全球特征和激发机制。解释Pi2脉动的理论主要有三种,即瞬态响应机制,亚暴电流楔理论和磁层空腔振荡理论。本文介绍了这三种理论的由来和发展,分析了每种理论在Pi2脉动研究中的贡献,并对Pi2脉动理论研究的进一步发展提出一些看法。 相似文献