初期の宇宙における原星形成
Naoki Yoshida1, Kazuyuki Omukai, Lars Hernquist
1Department of Physics, Nagoya University, Furocho, Chikusa, Nagoya, Aichi 464-8602, Japan. nyoshida@a.phys.nagoya-u.ac.jp
まとめ
科学者たちは最初の星の形成をシミュレートしました. ビッグバンの密度の変動は,巨大な原始恒星の前身である小さな原星を種にすることができます.
科学分野:
- コスモロジー・コスモロジーとは
- 天体物理学 天体物理学
- 恒星の進化について
背景:
- 初期の宇宙における最初の星 (集団IIIの星) の形成と性質は十分に理解されていません.
- 宇宙構造の成長は,重力の不安定性によって階層的に発生すると理論化されています.
- 観測の証拠は,初期の宇宙で巨大な原始星の存在を示唆しています.
研究 の 目的:
- 最初の星の形成メカニズムを研究するために,ab initioコンピュータシミュレーションを使用します.
- 膨張する宇宙内の原始ガスにおける原子および分子プロセスをモデル化するために.
主な方法:
- Ab initio コンピューターシミュレーションを開発しました.
- 原始的な星の形成をシミュレートし,原子と分子過程を追跡した.
- 膨張宇宙モデルが組み込まれました.
主要な成果:
- シミュレーションは,ビッグバンからの原始密度の変動が恒星形成を開始できることを示しています.
- 太陽の質量の約1%の小さなプロトスターは,これらの変動から形成される可能性があります.
- この原星は,その後の巨大な原始星の発展のための種として機能します.
結論:
- 原始密度の変動は,最初の星の形成を開始するための有効なメカニズムです.
- このシミュレーションは,初期の宇宙における巨大な星の起源を理解するための道筋を提供します.
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