銀河STIS123627+621755の赤道偏移z > 6に対する証拠
D Stern1, P Eisenhardt, H Spinrad
1Jet Propulsion Laboratory, California Institute of Technology, Pasadena 91109, USA. stern@zwolfkinder.jpl.nasa.gov
Nature
|December 16, 2000
まとめ
高赤偏移の銀河は,初期の銀河形成を理解するために不可欠です. STIS123627+621755の新しい観測は,それ以前に示唆された6.68の赤道移転と矛盾しており,それが近い可能性を示しています.
科学分野:
- 天文学と天体物理学について
- コスモロジー・コスモロジーとは
背景:
- 遠い銀河を特定することで,初期の銀河形成の直接的な洞察が得られます.
- 高赤偏移の銀河 (z > 5) は淡いので,信号と騒音の比率が低いため,データの解釈と識別が困難です.
研究 の 目的:
- 銀河の源であるSTIS123627+621755の赤偏移を調査するために,以前はz = 6.68.5の位置であると提案されていた.
- STIS123627+621755のスペクトルエネルギー分布と観測特性を高赤偏移で検証するために.
主な方法:
- 銀河源STIS123627+621755.5の光学および近赤外線観測を行った.
- 6,700 Åの銀河の検出可能性と1.2 μmの検出不能性を分析しました.
主要な成果:
- 銀河STIS123627+621755は6,700 Å.で検出されました.
- 銀河は1.2ミクロンで検出されませんでしたが,これはz ≈ 6.68.6の赤道移転の予想に反しています.
- 観測データは,STIS123627+621755.5の赤色偏移が6未満であることを強く示唆しています.
結論:
- 観測された光学および近赤外線データは,STIS123627+621755.5の以前に割り当てられた6.68の赤色偏移に異議を唱える.
- この結果は,STIS123627+621755の赤偏移の修正を必要とし,z < 6. に配置する必要があります.
- この研究は,非常に遠い銀河からのデータを識別し,解釈する際の困難を強調しています.
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