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Updated: Jul 12, 2026

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Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
原子炉で稼働する衛星からの一時的な粒子イベントの地磁気起源
まとめ
ガンマ線スペクトロメーターは,ソビエトの核衛星からの放射線を検出しました. これらのイベントは,ポジトロン消滅を含む,衛星の高度と大気密度に関連していた.
科学分野:
- 宇宙物理学の宇宙物理学
- 核工学は,原子力工学である.
- 天体物理学 天体物理学
背景:
- 1980年以来,太陽最大ミッション (SMM) 衛星のガンマ線スペクトロメーター (GRS) は一時的な現象を観測してきました.
- これらの出来事は,コスモス954と1402に似たものを含め,ソビエトの核反応器を搭載した衛星から放射される放射線と関連付けられています.
研究 の 目的:
- SMM GRSによって検出された一時的な放射線イベントの源を特定する.
- ソビエトの核衛星から放射される放射線の特徴と,地球の地磁場との相互作用を分析する.
主な方法:
- 太陽最大ミッション (SMM) 衛星のガンマ線スペクトロメーター (GRS) からのデータの分析.
- 検出された一時的な出来事と,ソビエト連邦の原子炉で動いている衛星の軌道経路と運用状態の相関.
- ガンマ放射,ポジトロン破壊線放射 (511 keV),および電荷粒子イベントの検出.
主要な成果:
- 18の異なるソビエトの核反応器搭載衛星が,一時的な出来事の源として特定されました.
- ガンマ放射線は,衛星がSMMから400~500km以内を通過したときに検出されました.
- 衛星から放出されたポジトロンと電子雲は,ポジトロン破壊線放射と電荷粒子イベントを通じて検出され,地磁場では保存時間は数十分まででした.
結論:
- 観測された一時的な現象は,ソビエトの核衛星からの放射に直接関係しています.
- 検出されたイベントの割合は著しく変化しました (1イベント/5日~>30イベント/日).
- イベントの発生率は,コスモス衛星の稼働高度と上層大気の密度に強く依存していました.
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