ウランの上の直接的な質量測定は,安定性の島へのギャップを埋めます
M Block1, D Ackermann, K Blaum
1GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstrasse 1, 64291 Darmstadt, Germany. m.block@gsi.de
Nature
|February 12, 2010
まとめ
ノベリウム (No) のような超重元素の質量を直接測定することで,核結合エネルギーを理解するための重要なデータが得られます. これらの正確な測定は,予測された安定性の島に向かって信頼できるアンカーポイントを提供します.
科学分野:
- 核物理学 核物理学とは
- 原子物理 原子物理学
- 化学 化学は化学です.
背景:
- 原子の質量と結合エネルギーは,核反応と元素合成に不可欠である.
- 超重元素の性質は,崩壊の連鎖から推論され,重大な不確実性を導入しています.
- 元素重さの限界を理解することは,核科学の重要な問題である.
研究 の 目的:
- トランスウラン核酸,特にノベリウム同位体 (252-254) の質量を直接測定する.
- 予測された安定性の島に近い元素の質量測定の精度を向上させるため.
- 核モデルと核力の理解のための信頼できるデータを提供すること.
主な方法:
- SHIPTRAP Penningトラップ質量スペクトロメーターを使用し,高精度の質量測定を行いました.
- 極小の生産速度 (一秒間に1原子未満) の課題を克服しました.
- 精度を損なうことなく,10個の原子番号による高度な直接質量スペクトロメトリ.
主要な成果:
- 約10 keV/c(2) (0.05 p.p.m.) の質量不確実性を達成しました. 相対的な精度) のために (252-254) No.
- トランスウラン領域に直接質量測定を拡張した.
- アクチニド領域の端にあるヌクリドの正確な質量値を確立した.
結論:
- 直接的な質量測定は,超重元素の腐敗連鎖再構築と比較して,より高い精度を提供します.
- これらの発見は,安定の島を探索するために不可欠なアンカーポイントを提供します.
- この研究は,ペニング・トラップ・マススペクトロメトリーの能力が,エキゾチックな原子核の調査に有効であることを証明している.
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