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レッドシフト z = 0.7 で高デュテリウムの豊富さ
J K Webb1, R F Carswell, K M Lanzetta
1School of Physics, University of New South Wales, Sydney, Australia.
Nature
|July 17, 1997
まとめ
原始デウテリウムから水素 (D/H) への測定は不一致です. この研究は,初期の宇宙における有意な不均一性を示唆する,新しい中間赤偏移D/H値を報告しています.
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
- 核物理学 核物理学とは
背景:
- 原始デウテリウムと水素の比率 (D/H) pは,宇宙学的質量密度パラメータ,omegaB.の重要な診断基準である.
- 既存の高赤偏差のD/H測定では,観測の不確実性による可能性のある重大な不一致が示されています.
- 不一致のD/H値は,宇宙学的モデルと銀河化学の進化に課題をもたらします.
研究 の 目的:
- 中間の赤偏差 (z = 0.7010) でD/H比の最初の測定を報告する.
- 原始的なD/Hの豊富さにおける潜在的な不均一性を調査する.
- 宇宙学的パラメータの推定における不一致を解決するのに役立つ値を提供する.
主な方法:
- 観測の不確実性を最小限にするために,中間の赤偏移 (z = 0.7010) のガス雲を選択しました.
- 選択したガス雲におけるデウテリウムと水素の比率 (D/H) を測定した.
- D/H値を,既存の高赤偏移測定と宇宙学モデルの文脈で分析した.
主要な成果:
- D/H値は (2.0 +/- 0.5) x 10[-4]で,z = 0.7010.10で測定されました.
- この測定値は,高い赤道移転の測定で観測された範囲の上端にあります.
- この結果は,他の観測結果と組み合わせて, (D/H) pにおける不均一性が少なくとも10倍に及ぶ可能性を示唆しています.
結論:
- この発見は,原始デウテリウムの豊富さにおける有意な不均一性の仮説を裏付けている.
- この不均一性は,宇宙学的探査としてD/H測定の解釈に意味を持つ.
- (D/H) pの変動の範囲と影響を確認するために,さらなる測定が必要である.
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