広島で原子爆弾の生存者にとって重要な距離で高速中性子を測定した
T Straume1, G Rugel, A A Marchetti
1University of Utah, 729 Arapeen Drive, Suite 2334, Salt Lake City, Utah 84108, USA. Straume1@aol.com
Nature
|August 2, 2003
まとめ
新しい測定は,広島原爆の生存者の中性子用量を検証し,長年の論争を解決しました. この研究は,ヒトの癌に対する放射線リスク評価を裏付けている.
科学分野:
- 核物理学 核物理学とは
- 放射線用量測定法による放射線用量測定法
- エピデミオロジー エピデミオロジー
背景:
- 原子爆弾の生存者のデータは,放射線によるヒトがんリスクの計算に不可欠です.
- ヒロシマでの潜在的に過小評価された中性子用量に関する二十年に渡る論争が存在しています.
- 熱中性子活性化の以前の測定は,推定よりも高い流動性を示唆しました.
研究 の 目的:
- ヒロシマの生存者への推定ニュートロン用量を検証するために.
- ニュートロン用量推定をめぐる論争を解決するために.
- 適切な距離での高速中性子用量に対する測定の検証を提供するため.
主な方法:
- ヒロシマの銅サンプルで高速中性子によって生成されたニッケル-63 (63Ni) の検出.
- 先進的な化学抽出と,非常に敏感な加速器質量スペクトロメトリーを使用した.
- 実験的な63Ni活性化と,中性子用量に基づく予測値を比較した.
主要な成果:
- 主に高速中性子 (>1 MeV) によって活性化される63Niを成功裏に検出しました.
- 測定された63Ni活性化と予測された中性子用量との間の良好な一致が観察されました.
- 生存者の位置に関係する距離 (900〜1500 m) で達成された検証.
結論:
- ヒロシマの生存者への中性子用量の最初の明確な測定検証を提供します.
- 放射能が誘発したヒトの癌の現在のリスク評価をサポートしています.
- 放射線用量再構築における重大な不確実性を解消する.
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