Are there Kronian electrons in the inner heliosphere
Are there Kronian electrons in the inner heliosphere
复制标题
日光层内层有克洛尼电子吗
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
H. Fichtner
中科院分区：
文献类型：
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作者：
D. Lange;H. Fichtner
上下文作为我们太阳系中最大的木星磁层，在文献中被视为少数MeV电子的主要来源，这些电子已被各种航天器测量。特别是，通过卫星监测系统获得的观测结果大大扩大了现有的数据库。目标。我们模拟了MeV电子在日光层的时间依赖性，三维调制模型的基础上的传输。为此目的，宇宙射线，木星和土星的电子源已被认为是第一次在一起模拟电子通量。讨论了沿着Cassini轨道的模拟电子强度。卡西尼号飞船已经两次经过木星（1992年，2004年），卡西尼号在2001年经过木星，并在2004年到达土星。木星上电子源的强度相对来说是众所周知的，并且有很好的模型。为了确定土星与木星的源强度，我们比较了木星/土星重叠能量范围内所有可用的航天器测量。我们研究的一般分布的克罗尼电子连续使用三个不同的强度的土星源在我们的模拟。此外，通过改变太阳风的速度场和各向异性扩散张量来考虑太阳活动的影响。方法.研究粒子扩散是特别相关的，因为在所使用的输运方程中真正未知的函数是扩散张量。木星和/或克罗尼亚电子适合于研究高能粒子的传输，因为源位置是众所周知的。结果在1兆电子伏的强度沿沿着的轨道和卡西尼号明显受到影响的存在下的克罗尼电子。结论.我们的结果表明，从克罗尼亚磁层的电子，作为第二大，不能忽略在非常低的MeV的能量范围。
Context. As the largest in our solar system the Jovian magnetosphere is treated in the literature as the dominant source of a fewMeV electrons, which have been measured by various spacecraft. In particular, observations obtained with Ulysses have significantly broadened the available data base. Aims. We simulated the transports of MeV electrons in the heliosphere on the basis of a time-dependent, three-dimensional modulation model. For this purpose the cosmic rays, the Jovian and the Saturnian electron sources have been, for the first time, considered together in the simulation of electron fluxes. The simulated electron intensities are discussed along the Ulysses and Cassini trajectories. The Ulysses spacecraft already passed by the planet Jupiter twice (1992, 2004), and Cassini passed by Jupiter in 2001 and reached Saturn in the year 2004. The strength of the electron source at Jupiter is relatively well known and well modelled. To determine the source strength of Saturn in comparison to that of Jupiter, we compared all available spacecraft measurements at Jupiter/Saturn in the overlapping energy range. We study the general distribution of Kronian electrons by successively using three different strengths of the Saturn source in our simulations. In addition, the effects of the solar activity are taken into account by varying the velocity field of the solar wind and the anisotropic diffusion tensor. Methods. Studying the particle diffusion is particularly relevant, because the really unknown function in the used transport equation is the diffusion tensor. The Jovian and/or Kronian electrons are suitable for studying the transport of energetic particles because the source locations are well known. Results. At 1 MeV the intensities along the Ulysses and the Cassini trajectories are clearly influenced by the presence of Kronian electrons. Conclusions. Our results reveal that the electrons from the Kronian magnetosphere, as the second largest, cannot be neglected in the very-low MeV energy range.