H2O吸収から6.34の赤色シフトでマイクロ波背景温度
Dominik A Riechers1, Axel Weiss2, Fabian Walter3,4
1I. Physikalisches Institut, Universität zu Köln, Köln, Germany. riechers@ph1.uni-koeln.de.
Nature
|February 3, 2022
まとめ
宇宙マイクロ波の背景温度は6.34で 遠くの銀河の水分を吸収して測定しました この発見は 標準宇宙論モデルを裏付けています
科学分野:
- 宇宙学
- 天体物理学
- スペクトロスコーピー
背景:
- 宇宙マイクロ波背景 (CMB) の温度測定は,初期の宇宙を理解するために不可欠です.
- 以前のCMB温度推定は,低赤偏移 (z < 3. 3) に限定され,一部はモデルに依存していました.
- 標準のラムダ・コールド・ダーク・マター (ΛCDM) モデルは,CMB温度と赤色シフト (T_CMB (1+z)) の間の特定の関係を予測する.
研究 の 目的:
- 高赤偏差 (z = 6.34) で CMB 温度を測定して ΛCDM モデルをテストする.
- 宇宙の物質支配時代を 探査するために
- 恒星爆発銀河の 熱的性質を調査する
主な方法:
- スターバースト銀河HFLS3のオーソ-H2O ((110-101) トランジションから観測されたサブミリメートル線吸収.
- 吸収測定のためのバックグラウンドソースとしてCMBを使用しました.
- スターバーストの活動による 水分の放射性ポンプを分析した
主要な成果:
- 検出された水分子の吸収は,z=6.34でCMBに対して
- z = 6.34 の CMB 温度 16.4 30.2 K (1σ) を推測した.
- 放射性ポンプによるCMB温度を下回る水分子の冷却を観察した.
結論:
- z = 6.34 で測定されたCMB温度は, ΛCDM 宇宙学によって予測された (1+z) スケーリングと一致しています.
- この研究は,直接的なCMB温度測定を,かなり高い赤偏移に拡張します.
- 銀河のスターバースト活動は,CMBに対する分子線の興奮に影響を与えます.
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