放射性超新星ガスの炭素の凝縮
D D Clayton1, W Liu, A Dalgarno
1Department of Physics and Astronomy, Clemson University, Clemson, SC 29634-1911, USA.
まとめ
超新星化学は,一酸化炭素を分解して炭素粉を作り,粉がそれよりも早く形成されるようにします.
科学分野:
- 宇宙化学 (コスモケミストリー)
- アストロケミストリー アストロケミストリー
- 恒星の進化について
背景:
- 超新星は重元素と塵の合成に不可欠な場所です.
- 炭素一酸化物 (CO) の形成は,通常,恒星の流出における自由な炭素原子の可用性を制限する.
- 隕石に含まれる太陽前粒子は,太陽系の初期状態の洞察力を提供します.
研究 の 目的:
- 膨張する超新星の中で炭素を含む分子と塵の形成につながる化学的プロセスを調査する.
- これらの種の豊富さを支配する方程式を数値的に解くために.
- 放射能が炭素化学と塵形成に及ぼす影響を調査する.
主な方法:
- 生物の多様性を支配する化学運動方程式の数値解.
- 膨張する超新星の内部における化学のモデリング.
- 放射能からのエネルギー電子の役割の分析.
主要な成果:
- 超新星放射能からのエネルギッシュな電子は,CO分子を解離し,自由な炭素原子を放出します.
- このプロセスは,塵の形成に利用可能な炭素原子の供給を増加させます.
- 炭素粉は,酸化によって破壊されるよりも,結合によってより速く成長します.
結論:
- スーパーノヴァの内部は,炭素塵の重要な源となる可能性があります.
- エネルギーのある電子によるCOの解離は,塵の形成を可能にする重要なメカニズムです.
- この発見は,プレソラー炭素固体の起源についての理解を変化させます.
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