銀河の表面密度の普遍性は,一つのダークヘロスケール-長さのダークヘロスケール内にある
Gianfranco Gentile1, Benoit Famaey, HongSheng Zhao
1Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281, B-9000 Gent, Belgium. gianfranco.gentile@ugent.be
Nature
|October 2, 2009
まとめ
銀河は,暗黒のハローのスケール長さの範囲内で一貫した明るく輝く物質の表面密度を示しています. この発見は,銀河における明るく輝く物質と暗黒物質の分布の間に強い相関があることを示しています.
科学分野:
- 銀河天文学は銀河天文学である.
- コスモロジー・コスモロジーとは
- 天体物理学 天体物理学
背景:
- 最近の研究では,様々な銀河のダークハロスケール長さ内のダークマターの表面密度の平均が一定であることが明らかになりました.
- このダークマターのスケーリング関係は,14マグニチュードの輝度範囲とハッブルシーケンス全体にわたる銀河に適用されます.
研究 の 目的:
- 暗黒のハロスケール-長さ内の光る物質の表面密度を調査するために.
- 暗黒物質に観測されたように,光る物質にも同様の定数が存在するかどうかを判断する.
主な方法:
- 銀河の光る物質の表面密度プロフィールの分析.
- 光る物質の表面密度と暗黒物質の表面密度をハロースケール長さで比較する.
主要な成果:
- 発光物質の表面密度は,暗黒のハロスケール長さの範囲内でも一定である.
- 光る物質からの重力加速は,この特徴的な半径で均一である.
- 全光と暗黒の物質の比率は変化しますが,この特定のハロスケール長さの範囲内では一定です.
結論:
- 銀河の明るい物質と暗い物質の閉じられた表面密度の間に有意な相関関係がある.
- この発見は,銀河のハロの中で物質の分布を制御する根本的な関係を示唆している.
- この定数は,銀河の形成と進化モデルに関する新しい洞察を提供します.
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