2つの中性子星の合併におけるストロンチウムの識別
Darach Watson1,2, Camilla J Hansen3,4, Jonatan Selsing3,5
1Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark. darach@nbi.ku.dk.
Nature
|October 25, 2019
まとめ
科学者は重元素であるストロンチウムを ニュートロン星が合体した後に 発見しました この発見は 宇宙の構成を理解するために 極めて重要な これらの元素の宇宙の起源として 中性子星の融合を 確認しています
科学分野:
- 核天体物理学
- 宇宙学
- 重力波天文学
背景:
- 鉄よりも重い元素の半分を合成する責任は天体物理学的rプロセス (急速の中性子捕獲) にあります.
- rプロセスの正確な宇宙の場所については,天体物理学では長い間議論されてきた.
- 中性子星の合併は,観測可能なキロノバを生成する主要な場所として理論化されています.
研究 の 目的:
- 新しく合成された r-プロセス元素を天体物理的な場所で特定する.
- 重元素の起源として ニュートロン星の融合を 確認するために
- GW170817の中性子星の合併後のキロノバAT2017gfoのスペクトルデータを分析する.
主な方法:
- キロノバAT2017gfoの詳細なスペクトルデータを再分析した.
- 重力波検出データ (GW170817) を利用して天体物理現象を特定した.
- 特定の元素のサインを特定するためのスペクトル分析.
主要な成果:
- キロノバAT2017gfoのスペクトルにおける中性子捕獲元素ストロンチウム (Sr) の決定的な識別.
- これは,そのようなイベントで特定のr-プロセス要素の最初の堅固な識別をマークします.
- この発見は 中性子星の融合における 重元素の合成を予測する 理論的モデルと一致しています
結論:
- ニュートロン星融合は,天体物理学的 r-プロセスにとって重要な場所として確認されています.
- ストロンチウムの検出は これらの宇宙衝突で重元素の形成の直接的な証拠を提供します
- この研究は 中性子星が 中性子に富んだ物質でできているという理解を 強化しています
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