矮星銀河の形成における恒星のフィードバック
Sergey Mashchenko1, James Wadsley, H M P Couchman
1Department of Physics and Astronomy, McMaster University, Hamilton, ON L8S 4M1, Canada. syam@physics.mcmaster.ca
Science (New York, N.Y.)
|December 1, 2007
まとめ
矮星銀河の恒星フィードバックは,中心の暗黒物質の密度プロファイルを平らにするガス運動を駆動し,シミュレーションと観測を並べて,コア-クースプの問題を解決します.
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
- 銀河の形成 銀河の形成
背景:
- 矮星銀河は,宇宙学的モデルに課題を提示し,特に予測された中央暗黒物質密度 (cusp) と観測された密度 (core) の間の不一致です.
- 超新星爆発や恒星風を含む恒星的なフィードバックは,矮星銀河の進化に影響を与え,このコア-クースプの問題を解決すると仮定されています.
研究 の 目的:
- 高解像度宇宙学シミュレーションを使用して,矮星銀河の構造に対する恒星フィードバックの影響を調査する.
- 星のフィードバックが観測可能な性質にどのように影響し,矮星銀河モデルにおけるコア-クースプ問題を解くかを評価する.
主な方法:
- 重要な物理的プロセスを捉えるのに十分な解像度で詳細な宇宙学的シミュレーションが行われました.
- シミュレーションは,恒星間ガスと暗黒物質の分布に対する恒星的なフィードバックの影響を直接モデル化しました.
主要な成果:
- 星のフィードバックは,矮星銀河内の恒星間ガスの大規模の大量運動を誘発することが示されました.
- これらのガス運動は重力潜在力の大きな変動をもたらした.
- 重力潜在力の変動は,中央の暗黒物質の密度の減少をもたらし,コアプロファイルを作成しました.
結論:
- 星のフィードバックは,矮星銀河の中央構造を形作るための重要なメカニズムです.
- 星からのフィードバックをシミュレーションに含めることで,理論的な予測と,矮星銀河のコア状暗黒物質密度プロフィールの観測的証拠をうまく調和させることができました.
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