2.34の赤偏移で,宇宙マイクロ波背景放射の温度です
R Srianand1, P Petitjean, C Ledoux
1IUCAA, Pune, India. anand@iucaa.ernet.in
Nature
|January 5, 2001
まとめ
宇宙マイクロ波の背景放射は,新しい測定で確認されたように,過去により暖かかった. この発見は,赤道移転とともに温度上昇を予測するホットビッグバンモデルを支持する.
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
- 原子物理 原子物理学
背景:
- ホットビッグバンモデルは,宇宙マイクロ波背景放射 (CMBR) の温度が赤道移転とともに上昇することを予測しています.
- 赤偏差 z=0時の現在のCMBR温度は,2.726 +/- 0.010 Kと正確に測定されています.
- 以前の研究では,より高い赤偏移でCMBR温度上の上限のみを設定することができました.
研究 の 目的:
- 特定の高赤偏移 (z = 2.3371) でCMBR温度を測定する.
- CMBRの温度進化に関するホットビッグバンモデルの予測をテストする.
- 以前の上限測定の限界を克服するために.
主な方法:
- 中性炭素の原子微細構造レベルからの吸収線を利用する.
- 分子水素の回転転移を分析する.
- シングルイオン化された炭素の微細構造の線を測定する.
主要な成果:
- 中性炭素の微細構造レベルからの吸収線が z = 2.3371.1. で検出されました.
- 分子水素と単離炭素の存在が確認されました.
- z = 2.3371のCMBR温度を6.0K~14Kの範囲に制限しました.
結論:
- CMBRは,初期の宇宙ではかなり暖かかった.
- 測定された気温は,ホットビッグバンモデルからの9.1Kの予測と一致しています.
- この研究は,高い赤偏移でCMBR温度を初めて直接測定したものです.
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