近くにある太陽のような星のスペクトルによる微細構造定数の変動の限界
Michael T Murphy1, Daniel A Berke1, Fan Liu
1Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia.
まとめ
微細構造定数 (α) は,電磁性に影響する. 研究者は近隣の恒星で α を測定し 10億分の1の変動を発見し 新しい宇宙基準を提示しました
科学分野:
- * 天体物理学と粒子物理学
- * 自然の基本的力について調べる
背景:
- * 微細構造定数 (α) の値は標準モデルによって説明されず,変動する可能性があります.
- * 恒星の吸収線はαに依存しますが,恒星の大気プロセスに影響されます.
研究 の 目的:
- * 近くの恒星における微細構造定数 (α) を正確に測定する.
- * 地元の宇宙の周辺にある α の潜在的変動を調査する.
- * 恒星のα測定のための正確な経験的基準を確立する.
主な方法:
- * 17個の太陽のような星 (太陽双子) から観測された正確な恒星吸収線波長.
- * 系統的エラーを最小限に抑えるために,太陽とほぼ同じ大気特性を有する星を選びました.
- * 微細構造定数 (α) の変動を検出するためにデータを分析した.
主要な成果:
- * 微細構造定数 (α) が50パーセック以内の10億分の1の大きさで変化している.
- * 恒星 α の測定では,10億分の12の集合精度を達成した.
- * 天体物理学的体系的効果を減らすために太陽双子を使うことの実現可能性を示した.
結論:
- * 微細構造定数 (α) は局所的な変化を示し,現在の物理モデルに挑戦しています.
- * この研究は,恒星環境におけるαを測定するための新しい,非常に正確なローカル・レファレンスを提供します.
- * 将来の研究は,α変異の性質と範囲を調査するために,これらの発見の上に構築することができます.
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