PAMELAによる宇宙線プロトンとヘリウムスペクトルの測定
O Adriani1, G C Barbarino, G A Bazilevskaya
1Department of Physics, University of Florence, I-50019 Sesto Fiorentino, Florence, Italy.
Science (New York, N.Y.)
|March 10, 2011
まとめ
精密な測定により,異なる宇宙線陽子およびヘリウムスペクトルが明らかになり,現在の銀河宇宙線モデルに挑戦しています. これらの発見を説明するために,新しい複雑な加速と伝播プロセスが必要である.
科学分野:
- 天体物理学 天体物理学
- 素粒子物理学 素粒子物理学について
- 宇宙線物理学 宇宙線物理学
背景:
- 宇宙線,主に陽子とヘリウム核は,銀河の過程を理解するために重要である.
- 精密な流量測定は,宇宙線加速と拡散のモデルを検証するために不可欠です.
研究 の 目的:
- 陽子とヘリウムスペクトルの精度測定を報告する.
- 1GVから1.2TVまでの硬度範囲を調査するために.
- スペクトル形を比較し,既存の宇宙線パラダイムに挑戦するために.
主な方法:
- 衛星による反物質物質探査と光核天体物理学 (PAMELA) 実験のためのペイロードを利用した.
- プロトンとヘリウムの流れの精度測定を行った.
- 幅広い硬度範囲内のスペクトルデータを分析した.
主要な成果:
- 陽子とヘリウムのスペクトルは,異なる形をしている.
- 単一の力法則モデルでは,観測されたスペクトルを適切に記述することができない.
- データは,標準的な宇宙線伝播モデルからの偏差を示しています.
結論:
- 観測されたスペクトル差異は,現在の超新星残骸加速と拡散的拡散パラダイムに異議を唱える.
- 宇宙線の複雑なスペクトル構造を説明するために,より洗練されたモデルが必要です.
- これらの発見は,銀河の宇宙線起源と輸送メカニズムの再評価を必要とします.
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