標準モデルの試験として微細構造定数の測定
Richard H Parker1, Chenghui Yu1, Weicheng Zhong1
1Department of Physics, 366 Le Conte Hall MC 7300, University of California, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|April 14, 2018
まとめ
物理学者はセシウム133の原子を使って 微細構造定数の最も正確な測定を達成しました この正確な値,α = 1/137.035999046 ((27) は,基本的な物理と潜在的な新しい粒子に関する新しい洞察を提供します.
科学分野:
- 原子物理学
- 量子測定法
- 基本定数
背景:
- 微細構造定数 (α) は,量子電動学の基本的無次元定数である.
- αの正確な測定は,粒子物理学の標準モデルの一貫性をテストします.
- 基本定数の不一致は 標準モデルを超えた新しい物理を 示す可能性があります
研究 の 目的:
- 微細構造定数の測定を 最も正確に行うために
- 高精度測定のための高度な物質波干渉測定技術を活用する.
- 実験結果と理論的予測を比較し,新しい物理学の探求を行う.
主な方法:
- ラムゼー・ボルドー干渉計でセシウム133原子を使用した.
- ブラッグ微分とブロッホ振動を含むマルチフォトン相互作用を利用した.
- 100億分の0.12の システム効果を制御した
主要な成果:
- 微細構造定数の最も正確な測定を記録した: α = 1/137.035999046 ((27) 精度2.0 × 10-10
- 物質波インターフェロメトリーにおける 体系的な効果に対する 前例のない制御を証明した.
- 測定の精度は,電子回転磁気異常 (g-2) データとの比較を制限しています.
結論:
- 新しいαの測定は量子電動学の厳密なテストを提供します.
- 標準モデルで比較すると,電子g-2データと2.5σの緊張は,ミオンg-2異常の説明としてダークフォトンを排除する.
- この発見は,ダークセクター候補と電子の基底構造を含む,標準モデルを超えた物理学の探索のための潜在的な道を示唆しています.
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