在IBEX能量中性原子地图中,外层日球的结构和光谱变化
H O Funsten1, F Allegrini, G B Crew
1Los Alamos National Laboratory, Los Alamos, NM 87545, USA. hfunsten@lanl.gov
Science (New York, N.Y.)
|October 17, 2009
概括
星际边界探测器 (IBEX) 揭示了在日光的不同能量质子群体. 一个突出的带特征,可能靠近当地的星际磁场,显示的离子压力明显高于全球分布的人口.
科学领域:
- 空间物理 空间物理
- 太空物理学 太空物理学
- 天体物理学 天体物理学
背景情况:
- 太阳层是太阳风终结冲击和当地的星际介质之间的区域.
- 能量中性原子 (ENAs) 提供了关于层中的等离子体状况的见解.
研究的目的:
- 分析由星际边界探测器 (IBEX) 获得的来自日层的ENAs全天图像.
- 描述能量质子群体及其在日光层内的空间分布.
主要方法:
- 使用IBEX全天空 ENA流量图.
- 分析了0.2到6千电子伏特范围内的日光层质子群的光谱特征.
主要成果:
- 鉴定出不同的非热层质子群体,其光谱特征与日食度相关.
- 观察到一个全球分布的终结冲击加热质子群.
- 检测到一个带状的特征,天空中的弧形,可能靠近当地的星际磁场方向.
- 量化了带的非热离子压力-厚度乘积 (70-100 pN/cm2 AU),显著超过全球分布的人口 (30-60 pN/cm2 AU).
结论:
- 太阳层含有复杂的能量质子群体,包括一个主要的带状特征.
- 带的较高的离子压力表明,在日光层中存在着明显的物理过程或相互作用.
- IBEX观测为了解日球与当地的星际介质的相互作用提供了关键数据.
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