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Updated: Jul 4, 2026

07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
遠い宇宙の分子からの変数プロトン対電子質量比に対する強い限界
Michael T Murphy1, Victor V Flambaum, Sébastien Muller
1Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Mail H39, Post Office Box 218, Victoria 3122, Australia. mmurphy@swin.edu.au
まとめ
科学者たちは,クエザールからのアンモニアスペクトルを使用して,陽子対電子質量比 (mu) をテストしました. この研究は,muの変動に関するこれまでで最も強い天体物理学的制約を提供し,それが宇宙時間における定数であることを示しています.
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
- 素粒子物理学 素粒子物理学について
背景:
- 素粒子物理学の標準モデルは,基本定数は不変であると仮定しています.
- クワザーの吸収線のような宇宙学的観測は,これらの定数を膨大な距離と時間尺度でテストすることを可能にします.
- 陽子と電子の質量比 (mu) は,変化に敏感な重要な基本定数である.
研究 の 目的:
- 分子スペクトロスコーピーを用いて,陽子と電子の質量比 (mu) を測定する.
- クエーサーの視線を用いて,宇宙的時間におけるmuの潜在的な変動を制限する.
主な方法:
- ミュウに非常に敏感なアンモニアの逆転トランジションを使用しました.
- クワザールB0218+357からの高品質のアンモニアスペクトルを,実験室の回転スペクトルと比較した.
- クワザール視線に沿った分子雲の吸収線を分析し,ミューを検出しました.
主要な成果:
- このスペクトロスコーピテクニックを用いたMuの最初の詳細な測定を発表した.
- ラボ値からmuの制限された相対偏差は,Deltamu/muの値<1.8 x 10(-6) で95%の信頼度.
- 宇宙の現在の年齢の約半分で,muに関するこれまでの最強の天体物理的制約を達成しました.
結論:
- 陽子と電子の質量比 (mu) は,宇宙時間における驚くべき安定性を示しています.
- アンモニア光譜は,基本的な物理定数をテストするための強力なツールです.
- 将来の高品質のアンモニア観測は,mu測定における不確実性をさらに減らすことができます.
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