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核分裂における角運動量生成
J N Wilson1, D Thisse2, M Lebois2
1Université Paris-Saclay, CNRS/IN2P3, IJC Laboratory, Orsay, France. jonathan.wilson@ijclab.in2p3.fr.
Nature
|February 25, 2021
まとめ
核分裂の断片は 分裂後にモメンタムを得ます 核分裂後のスピン生成は 頸部中の核運動によって引き起こされ,以前の理論に異議を唱え,核反応炉物理と超重元素の研究に影響を与えます
科学分野:
- 核物理学
- 核分裂
- 量子力学
背景:
- 重い原子核が 核分裂の後に 重要な角運動量で出現するのは 長い間謎でした
- 既存の理論では,角運動量は,集合的振動モードを通じて核分裂 (前割れ) 前に生成される.
- 実験データの欠如は,角運動量生成の競合する理論の決定的な検証を妨げています.
研究 の 目的:
- 核分裂断片における角運動量生成のメカニズムを調査する.
- スピンは割れ前か割れ後のものかを決定する.
- 原子核分裂における角運動量生成の新しいモデルを提案する.
主な方法:
- 核分裂における断片スピンの包括的な実験分析.
- フラグメントパートナーのスピン間の相関分析
- 断片スピンの質量と電荷依存性に関する研究.
主要な成果:
- 分裂断片のパートナー間のスピンは有意な相関関係が見つかりませんでした.
- 断片の回転は重量に依存しており,歯の分布を示しています.
- フラグメントスピンは,パートナーの核の質量または電荷に顕著な依存を示さなかった.
結論:
- 核分裂の角運動は,核が分裂した後に発生する.
- 提案されたモデルは,破裂した首のニュクレオン運動によって生成された独立したトルクを示唆しています.
- この発見は原子炉物理学,中性子に富んだ同位体構造,超重元素合成に 影響を及ぼしている.
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