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双子中性子星の合併における重元素の起源は,重力波のイベントから生じる
Daniel Kasen1,2, Brian Metzger3, Jennifer Barnes3
1Departments of Physics and Astronomy, and Theoretical Astrophysics Center, University of California, Berkeley, California 94720-7300, USA.
Nature
|November 3, 2017
まとめ
中性子星の合併は,急速な中性子捕獲 (rプロセス) 核合成によって,金やプラチナのような重元素を生成する. キロノヴァと呼ばれる これらの融合からの熱的光は この宇宙元素の生成の 最初の直接的な証拠を提供します
科学分野:
- 天体物理学
- 核物理学
- 宇宙学
背景:
- 鉄よりも重い元素の起源は 天体物理学では長い間謎でした
- 理論的なモデルは,急速な中性子捕獲 (rプロセス) 核合成の潜在的な場所として中性子星の合併を示唆している.
- 新しく合成された重元素の放射性崩壊は キロノヴァ つまり熱的光を発すると予測されています
研究 の 目的:
- キロノヴァの電磁気放出を 詳細にモデル化する
- キロノヴァ観測から噴出物質,速度,組成を導出できるようにする.
- 重元素の宇宙生成における 中性子星の合併の役割を調査する
主な方法:
- キロノヴァの電磁気放出を予測するための詳細なモデルを開発した.
- GW170817の光学および赤外線データとモデルの予測を比較した.
- 質量,速度,元素の組成を含むエジェクトの推論された性質.
主要な成果:
- GW170817から観測された電磁放射線は キロノヴァと一致します
- 軽量 (A < 140) と重量 (A > 140) の2つの異なるエジェクタ要素の存在を推測した.
- 射出された質量と推論された融合率は,中性子星の融合が r-プロセス元素の主要な源であることを示唆している.
結論:
- 中性子星の融合は r プロセスによる重元素の生産のための重要な宇宙の場所として確認されています.
- GW170817のような キロノヴァ観測は 重元素の核合成に関する 重要な洞察力を提供します
- この研究は,宇宙における元素の創造を理解するために,キロノヴァを分析するための枠組みを確立しています.
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