ガンマ線爆発の光学偏極化の初期段階は,発光後の輝きによるものです
Carole G Mundell1, Iain A Steele, Robert J Smith
1Astrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead, CH41 1LD, UK. cgm@astro.livjm.ac.uk
まとめ
ガンマ線爆発の光学偏振を測定しました. 後照の発生時の低偏振は,標準的なガンマ線爆発モデルにおける大規模な磁場を排除する.
科学分野:
- 天体物理学 天体物理学
- 高エネルギー天文学 高エネルギー天文学
背景:
- ガンマ線爆発 (GRB) は,宇宙で最も明るい爆発です.
- GRBの放出機構と磁場構造を理解することは,理論モデルをテストするために不可欠です.
研究 の 目的:
- ガンマ線爆発 (GRB) の光学偏振を研究するために.
- GRBを発射する領域の磁場特性を制限するために.
主な方法:
- GRB 060418の光学偏振測定は,リバプール望遠鏡のリング偏振計を用いて行われました.
- 後照明の明るさの衰退率と組み合わせた偏光データの分析.
主要な成果:
- GRBの203秒後に8%未満の極化という堅固な上限値が得られました.
- この低い極化度は,火球の減速時間と一致した.
結論:
- 観測された低い極化と崩壊速度は,標準的なGRBエジェクトモデルを制約する.
- 結果は,GRB 060418.18の放射領域に,大規模な有秩序な磁場が存在することを排除しています.
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