螺旋型の惑星間磁場:極性と日光斑の周期の変化

L Svalgaard, J M Wilcox

Science (New York, N.Y.)

|October 4, 1974

まとめ

宇宙船のデータは,惑星間磁場がパーカーから偏っていることを明らかにした.

科学分野:

* 太陽物理学と宇宙プラズマ物理学.
*ヘリオスフィアの磁場と太陽風のダイナミクスを研究する.

背景:

* 惑星間磁場 (IMF) は通常,パーカーのスパイラルモデルで記述される.
* 太陽の最大条件中の観測は,IMFの構造を理解するために不可欠です.

研究の目的:

* ソーラーマキシマム年におけるパーカーのモデルからIMFの方向偏差を分析する.
* 遠方方向と太陽の極性方向の角差を定量化するために.

主な方法:

* IMFの地球近傍の宇宙船によるインシトゥ測定の分析.
* 1968年 (太陽最大) の間の対極性の平均フィールド方向の計算.

主要な成果:

* 観測された平均フィールド方向間の包括的角度は168度でした.
* これは,パーカーの古典的なスパイラルフィールドモデルで予測された180度から逸脱しています.
* 偏差は,太陽のサイクルに関連した潜在的な変動を示しています.

結論:

* パーカーの古典的なIMFモデルには,特に太陽の最大期に精細化が必要である.
*観測された角偏差は,ヘリオスフィアの磁場構造に影響を与える動的プロセスを示唆しています.
* この現象の太陽サイクル依存性を理解するためにさらなる研究が必要である.

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