Effect of Solar Cycle Activity on High Energy Proton of Inner Radiation Belt in the Low Altitude Region
-
摘要: 利用NOAA-15卫星1998年到2011年近13年的高能质子全向通量观测资料, 分析了一个太阳活动周内, 低高度内辐射带高能质子通量的分布变化特性及其物理原因, 比较了观测结果与AP8模型的不同. 研究表明, 低高度内辐射带高能质子通量与太阳活动水平的反相关关系与磁壳参数L值及磁场B值有关; L值越低, B值越大的空间点, 其高能质子通量与太阳活动水平的反向相关性越明显. 高能质子通量随太阳活动水平的变化存在明显滞后现象, L值越高、 B值越小的空间点, 滞后现象就越明显, 滞后严重时可以达到一年左右的时间; 这种滞后现象反映出低高度内辐射带高能质子的源与损失达到平衡是一个中长期过程. 通过与AP8模型计算结果的比较分析可以看出, 利用AP8模型时, 仅考虑地磁场长期变化对质子通量的影响可能会夸大低高度内辐射带局部高能质子通量的增强.Abstract: The NOAA-15 high energy proton observation from 1998 to 2011 is used to analyze the effect of solar cycle activity on high energy proton flux. The statistic research indicates that there is an inverse correlative relationship between the proton flux in inner radiation belt and solar activity. This anti-correlation is related to geomagnetic coordinates L and B, and more significant with the increasing of L and decreasing of B. There is also a phase lag between the solar activity and the proton flux. This hysteresis effect is more obvious in the region with smaller L or larger B. The lag can reach one year in some regions. This hysteresis effect means it takes a long time to reach the dynamic balance between the source and the loss for the proton of inner radiation belt in the low altitude region. The unbalance between the source and loss is the reason why the intensity of proton flux at the same solar activity is different. The comparison with the result of AP8 model indicates the energetic proton flux from AP8 is higher than the satellite's observation in the region with large B, which suggests that the AP8 model may overstate the proton flux enhancement at inner radiation belt in the low altitude region if only the long-term variation of magnetic field is considered.
-
Key words:
- High energy proton /
- Radiation belt /
- Solar activity /
- South Atlantic Anomaly (SAA)
-
[1] Fung S F. Recent development in the NASA trapped radiation models[G] //Radiation Belts. AGU Books Board, 1997. 79-91 [2] Fang Xiaohua, Pu Zuyin. Drift shell tracing method and the secular variation of inner radiation flux[J]. Chin. J. Space Sci., 2000, 20(2):150-158. In Chinese (方晓华, 濮祖荫. 漂移壳追踪方法与内辐射带的长期变化[J]. 空间科学学报, 2000, 20(2):150-158) [3] Pu Z Y, Xie L. Drift shell tracing and secular variation of inner zone high energy proton environment in the SAA[J]. Adv. Space Sci., 2005, 36:1973-1978 [4] Xie Lun, et al. The study of the secular variation of high energy proton environment of inner radiation in SAA. Sci. China: D, 2005, 35(7):658-663. In Chinese (谢伦, 等. 南大西洋异常区内辐射带高 能质子辐射环境长期变化的研究. 中国科学D辑, 2005, 35(7):658-663) [5] Zang Zenqun. The effect of the earth magnetic field long term changes on the calculation of proton flux in the radiation belts[J]. Chin. J. Space Sci., 1997, 17(1):34-39. In Chinese (臧振群. 地磁场的长期变化对辐射带质子通量计算的影响[J]. 空间科学学报, 1997, 17(1):34-39) [6] Le Guiming, Ye zonghai, Zhou guocheng. Low altitude satellite orbit radiation belt particle environment variation due to geomagnetic field long term variation[J]. Chin. J. Space Sci., 2001, 21(3):238-245. In Chinese (乐贵明, 叶宗海, 周国成. 地磁长期变化引起的低高度卫星轨道辐射带粒子 环境的变化[J]. 空间科学学报, 2001, 21(3):238-245) [7] Jiao Weixin, Pu Zuyin. The radiation environment within the south Atlantic anomaly region and the calculating trapped particles fluxes for low orbital satellite[J]. Chin. J. Geophys., 1999, 42(2):163-168. In Chinese (焦维新, 濮祖荫. 南大西洋地磁异常区的辐射环境与低轨卫星粒子辐射通量计算[J]. 地球物理学报, 1999, 42(2):163-168) [8] Sawyer D M, Vette J I. AP-8 Trapped Radiation Environment for Solar Maximum and Solar Minimum[R]. NSSDC/WDC-A-R&S 76-06, 1976 [9] Vette J I. The AE-8 Trapped Electron model Environment[R]. NSSDC/WDC-A-R&S 91-24, 1991 [10] Evans D S, Greer M S. Polar Orbiting Environmental Satellite Space Environment Monitor 2 Instrument Descriptions and Archive Data Documentation[R]. Boulder, Colorado: NOAA Technical Memorandum. 1.4, Space Environment Laboratory, 2004 [11] Roederer J G. Introduction to trapped particle flux mapping, in radiation belts[G]. Geophys. Monogr. 97 Washington D C: American Geophysical Union, 1996. 149-153 [12] Roederer J G. Dynamics of Geomagnetically Trapped Radiation[M]. Berlin: Springer-Verlag, 1970 -
-
计量
- 文章访问数: 3538
- HTML全文浏览量: 230
- PDF下载量: 1220
-
被引次数:
0(来源:Crossref)
0(来源:其他)
下载:
