超許容ガモウ-テラー分解のダブルマジック核 100Snn
C B Hinke1, M Böhmer, P Boutachkov
1Physik Department E12, Technische Universität München, D-85748 Garching, Germany.
Nature
|June 23, 2012
まとめ
研究者は,最も重い二重魔法の核であるtin-100の崩壊を測定しました. この研究は,許容された核ベータ崩壊における最大のガモウ-テラー強さを明らかにし,その超許容された性質を確認しました.
科学分野:
- 核物理学 核物理学とは
- 原子の構造 原子の構造
- 量子力学は,量子力学という
背景:
- 原子核は,核 (陽子と中性子) の相互作用から生じる"魔法の数"と結びついた殻構造を示しています.
- ベータプラス崩壊は,陽子から中性子への変換を含み,ポジートロン-中性子ペアを放射します. トランジションは,放射された粒子のスピンに基づいて,ガモウ-テラーまたはフェルミに分類されます.
研究 の 目的:
- 陽子中性子の比率が等しい,二倍マジックな核であるtin-100 (100Sn) のベータ分解特性を調査する.
- 100Snの半減期と崩壊エネルギーを測定し,その崩壊特性を理解する.
主な方法:
- 100Sn.の半減期と崩壊エネルギーの実験的測定.
- 100Sn.のβ分解におけるガモウ-テラー移行強度分布の分析
主要な成果:
- 100Sn.のβ分解の半減期と分解エネルギーを決定しました.
- 大量の衰退エネルギーによる衰退強度の有意な割合を観測した.
- 許容された核ベータ崩壊における最大のガモウ-テラー強度を測定し,それを"超低"移行として識別した.
結論:
- 100Snのβ分解は,前例のない強さで,超許容のGamow-Teller移行を示しています.
- 近代の大規模なシェルモデルの計算は,子核であるインジウム-100 (100In) の観測された高強度および低い状態を正確に再現します.
- この発見は,核構造モデルを精錬し,核の基本的なプロセスを理解するための重要なデータを提供します.
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