衛星による原子炉の観測は,風船搭載のガンマ線望遠鏡で行われた
まとめ
高エネルギーガンマ線は,1988年に4つの核衛星から検出されました. これらの一時的な衛星信号は,ガンマ線天文学的背景に関する新しいデータを提供した.
科学分野:
- * 天体物理学と宇宙科学
- * 高エネルギー物理学
背景:
- *宇宙からのガンマ線の検出は,天体現象を理解するために重要である.
- * 過去の研究は,一時的な人工源に関する限られたデータで,天のガンマ線源を特定することに焦点を当てていました.
研究 の 目的:
- * 原子力衛星からの一時的なガンマ線信号の検出を報告する.
- * 持続時間,光度,エネルギースペクトルを含むこれらの信号の特徴を分析する.
- * このような人工源が,ガマ線背景全体に与える貢献度を評価する.
主な方法:
- * オーストラリアのアリス・スプリングス上空35kmの高さで,風船で運ばれたコンプトン・ダブル・ガンマ線望遠鏡を利用した.
- * 1988年4月15日に30時間の観測データを収集しました.
- *4つの原子力衛星 (コスモス1900とコスモス1932が特定された) の一時的な信号を分析した.
主要な成果:
- *0.3〜8メガ電子ボルト (MeV) のエネルギーを持つ4つの一時的なガンマ線信号が検出されました.
- * 観測された信号の持続時間は21秒から113秒で,軌道の高度は260キロから800キロメートルに相当する.
- *計算された光度 (3.9 ± 1.0) x 10^15と (1.30 ± 0.32) x 10^16のフォトン/秒.
- * エネルギースペクトルは,指数 2.4 ± 1.4 の指数を持つ指数関数に適合した.
結論:
- *検出された一時的なガンマ線現象は,原子力衛星から発生した.
- * これらの人工的な源は,ガンマ線天文観測における背景騒音に寄与する.
- *この発見は,天体と人工のガンマ線源を区別することの重要性を強調しています.
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