NGC 253 の巨大な磁星フレアとして解釈された明るい γ 線フレア
D Svinkin1, D Frederiks2, K Hurley3
1Ioffe Institute, St Petersburg, Russia. svinkin@mail.ioffe.ru.
Nature
|January 14, 2021
まとめ
マグネタールから発生する 巨大なフレアは 強い磁気を持つ中性子星で 強力なX線とガンマ線を発射します 研究者らはGRB 200415Aを観測し,NGC 253銀河の磁星からの巨大なフレアであると特定しました.
科学分野:
- 天体物理学
- 高エネルギー天体物理学
- 中性子星物理学
背景:
- 柔らかいガンマ線反射器 (SGR) は,超強い磁場を持つ磁星とニュートロン星に起因する,硬いX線と柔らかいガンマ線の爆発的な放出を示します.
- 10^44から10^46エルグの エネルギーを有する
- 中性子星の合併に関連した 短いガンマ線爆発 (GRB) と特徴を共有する 巨大なフレアもあります
研究 の 目的:
- ガンマ線爆発GRB 200415Aを分析し,その起源を決定する.
- 巨大なフレアとガンマ線爆発の関係を調べるためだ
- マグネタールからのエネルギー放出を特徴づける.
主な方法:
- GRB 200415Aは,星爆発銀河NGC 253の特定の領域に位置しています.
- GRB 200415Aイベントのスペクトルおよび時間特性の分析.
- GRB 200415Aのエネルギー出力を,既知の磁石の巨大フレアと比較する.
主要な成果:
- GRB 200415Aは,約350万パーセクの距離にあるNGC 253に位置づけられました.
- 爆発は,0.2秒にわたって柔らかく続く鋭い,ミリ秒スケールのハードスペクトルを示しました.
- GRB 200415Aの放出されたエネルギー (約. 1.3 × 10^46 erg) は,銀河磁星からのスーパーフレアに匹敵する.
結論:
- GRB 200415Aは,NGC 253内の磁星から発生した巨大なフレアとして特定されています.
- この観測は磁石の巨大フレアと 特定のガンマ線爆発との関連を強くしています
- この研究は,これらの極端な天体物理現象を説明するために,磁星モデルのためのさらなる証拠を提供します.
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