キロノヴァAT2017gfo/GW170817における球形の対称性
Albert Sneppen1,2, Darach Watson3,4, Andreas Bauswein5
1Cosmic Dawn Center (DAWN), Copenhagen, Denmark. a.sneppen@gmail.com.
Nature
|February 15, 2023
まとめ
ニュートロン星が合体すると キロノバが生まれます AT2017gfoの分析は,高度に球状のキロノヴァを明らかにし,非球状のエジェクタを予測するモデルに挑戦し,新しい物理学の関与を示唆しています.
科学分野:
- 天体物理学
- 核物理学
- 重力波天文学
背景:
- ニュートロン星の合併は キロノバを生じます 重元素で濃縮された火球として観測できます
- キロノヴァの幾何学は 超密度の物質とブラックホール形成の エネルギーについて 洞察力を与えてくれます
- 既存の水力学モデルでは,主に合併によるアスフェリックエジェクトを予測しています.
研究 の 目的:
- キロノヴァAT2017gfoの幾何学を決定する
- キロノバエジェクトの形状に影響を与える要因を調査する.
- 理論的な合併モデルと観測データを調和させる.
主な方法:
- AT2017gfoにおけるストロンチウム (Sr+) P Cygniスペクトルの分析
- キロノヴァのブラックボディスペクトルの特徴
- 線形分析は,既知の傾斜角度と組み合わせた.
主要な成果:
- キロノバAT2017gfoは初期の段階で非常に球状の幾何学を示した.
- スペクトルの特徴と傾斜角度を用いた独立した分析は,この球体性を確認した.
- 放射性分解だけでは,観測された球状の噴出物を説明することはできません.
結論:
- AT2017gfoの球状の幾何学は,磁気風やブラックホール・ディスク・ジェットからのエネルギー注入を示唆している.
- 排泄物中の元素の均一な分布のために,まだ特定されていない追加のプロセスが必要である可能性が高い.
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