中性子星の合併の無線対称
G Hallinan1, A Corsi2, K P Mooley3
1Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA. gh@astro.caltech.edu.
まとめ
科学 者 たち は,二重 ニュートロン 星 (GW170817) の 合併 から 放射 信号 を 検出 し,その 合併 に 関する 洞察 を 明らか に し まし た
科学分野:
- 天体物理学
- マルチメッセンジャー天文学
- 重力波天文学
背景:
- 二重中性子星の合併イベントGW170817からの重力波の検出は,そのような宇宙衝突の最初の直接的な証拠を提供しました.
- 電磁放射線の同時検出は,約40メガパーセック離れた銀河のNGC 4993の合併の位置を確認しました.
研究 の 目的:
- GW170817の合併のエネルギーと環境を調査する
- 重力波の対称性を特定し特徴づけること
- 合併後の提案されたモデルを区別する.
主な方法:
- 合併の16日後に現れた無線対照源の検出
- 合併エネルギーと環境を診断するための無線放射の分析
- 非常に長いベースラインインターフェロメトリ (VLBI) を使用して,破片の幾何学と角速度測定を行います.
主要な成果:
- GW170817の発生から16日後に 放射性同源が検出されました
- 観測された無線放射は,軸外超相対論ジェットか,軽度の相対論エジェクトのと一致する.
- 100日以内にこれらの2つのモデルを区別することが期待されています.
結論:
- 双重中性子星の融合の物理を理解するために 重要なデータを提供します
- 将来の観測により,残骸の幾何学と角速度をVLBIで直接測定することができます.
- この研究は 極端な宇宙現象を解明する マルチメッセンジャー天文学の力を 強調しています
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