200年前のSgr AのX線極化証拠
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PubMedで要約を見る
まとめ
この要約は機械生成です。射手 A* と いう 銀河 の 過去 の 活動 を 極化 さ れ た X 線 の 観測 から 見いだす
科学分野
- 天体物理学
- X線天文学
- ポラメトリー
背景
- 銀河系の中央のブラックホールである Sagittarius A* (Sgr A) は,現在静止状態にある.
- 周囲のガスからのX線反射は,Sgr A*の過去の燃焼活動を探査することができます.
- 過去の観測はX線放射の反射シナリオを示唆した.
研究 の 目的
- 銀河の中心からの X線放射を調査する
- 反射シナリオを確認し,Sgr A*の過去の明るさを研究する.
主な方法
- イメージングX線極測探査機 (IXPE) を使用する.
- Sgr A*近くの分子雲の方向に偏光X線放射を観測する.
主要な成果
- 31%±11%の偏り度が測定されました.
- -48°±11°の偏角を測定した.
- 結果は,Sgr A*を排出源と一致しています.
結論
- この発見はSgr A*のX線反射モデルを支持する.
- 暗示Sgr A*のX線明るさは200年前まで,シーファート銀河と少し似ていた.
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