太陽周期における太陽のメリディアン流の変動

David H Hathaway¹, Lisa Rightmire

¹NASA Marshall Space Flight Center, Huntsville, AL 35812, USA. david.hathaway@nasa.gov

Science (New York, N.Y.)

|March 13, 2010

まとめ

太陽の磁場と太陽光斑の周期に不可欠な太陽の表面の流れは,太陽と太陽球観測所のデータを用いて測定されました. この流れは太陽の最小値の間より速く,現在の太陽活動異常を説明する可能性がある.

科学分野:

ソーラー物理学ソーラー物理学
ヘリオフィジックスヘリオフィジックス
プラズマ物理学プラズマ物理学

背景:

赤道から極点までの地表電流である太陽の南極流は,極の磁場強度と日光斑サイクル強度に影響を与えます.
この流れを理解することは,太陽の活動とその影響を予測する鍵です.

研究の目的:

磁気特性を用いて太陽のメリディアン流の速度を測定する.
流速が緯度や太陽周期相によってどのように変化するかを分析する.

主な方法:

ソーラー・アンド・ヘリオスフィア・オブザーバリー (SOHO) のデータを活用した.
様々な緯度における表面流動速度を測定するために,磁気特性を追跡した.
太陽の最大値と最小値の流れ速度を比較した.

主要な成果:

メリディナルの流れは,75度までの測定されたすべての緯度で極に向かって流れている.
太陽サイクル最小値の流れ速度は,太陽サイクル最大値と比較して,太陽サイクル最小値の流れ速度はより大きい.
現在の太陽光最小値へのアプローチは,以前の最小値よりもかなり速い流れを示しました.

結論:

太陽の南極流は高緯度まで広がり,極に届く可能性が高い.
メリディナル流速の変動は,太陽周期の相と相関しています.
現在の最小値に近い加速した流れは,その異常な特性を説明するかもしれない.

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