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Updated: Jul 12, 2026

11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
まとめ
パルサーの強度の変動は,星間介質の不規則性を示唆しています. これらのシンチレーションは,パルサーの角度サイズは0.3マイクロ弧秒未満であり,無線源の角度直径に影響を及ぼすことを示しています.
科学分野:
- 天文学と天体物理学について
- ラジオ天文学 ラジオ天文学
背景:
- パルサーは,電磁放射線のビームを放射する,急速に回転する中性子星です.
- 星間介質 (ISM) は,ラジオ波の伝播に影響を与え,観測された強度の変動を引き起こす可能性があります.
研究 の 目的:
- 特定のパルサーからのパルス式無線信号の時間変動を調査する.
- 観測された変動が恒星間シンチレーション理論と一致するかどうかを判断する.
主な方法:
- パワースペクトル,モジュレーション指数,周波数分布,およびデコレレーション周波数の分析.
- 星間シンチレーション効果のモデリング.
主要な成果:
- パルサーの強度の変動は,星間シンチレーションと一致しています.
- ISM不規則の推定スケールサイズ: ~10^4 km.
- 不規則点までの推定距離: ~70パーセック.
- パルサーの推定角径:<0.3 x 10^-5 弧秒.
結論:
- 星間介質の不規則性は,観測されたパルサーの強度の変動を引き起こします.
- この研究は,パルサーの角サイズと,点射線源の明らかな角拡大に関する制約を示している.
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