GRB 090102からの10%の偏光光学放射は,GRB 090102からの
I A Steele1, C G Mundell, R J Smith
1Astrophysics Research Institute, Liverpool John Moores University, CH41 1LD, UK. ias@astro.livjm.ac.uk
Nature
|December 17, 2009
まとめ
ガンマ線爆発 (GRB) の初期の光学放射は,10%の極化を示しています. これは,膨張する火球から発生した大規模な磁場を示し,GRBジェットの組成を明確にします.
科学分野:
- 天体物理学 天体物理学
- 高エネルギー天体物理学
背景:
- ガンマ線爆発 (GRB) ジェットの組成と磁場構造は十分に理解されていません.
- 2つのモデルが存在します:弱い,絡み合ったフィールドを持つバリオンが支配するジェット,または中央エンジンから大規模な磁場を持つジェット.
研究 の 目的:
- GRBジェットにおける磁場の役割を,早期の放出偏振を測定することによって調査する.
- 極化特性に基づいてGRBジェットモデルを区別する.
主な方法:
- GRB 090102からの初期の光学放射の偏振を測定しました.
- 観察のために60秒の曝露時間を利用しました.
主要な成果:
- GRB 090102.2の初期の光学放射で10 +/- 1%の偏振が検出されました.
- この結果は,膨張する火球の中で発生する大規模な磁場の存在を示唆している.
結論:
- この発見は,GRBジェットが大規模な磁場でスレッドされているモデルを裏付けている.
- 初期の光学極化測定は,GRBジェット物理と磁場起源を理解するために不可欠です.
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