ラジオバーストの宿主銀河

E F Keane^1,2,3, S Johnston⁴, S Bhandari^2,3

¹Square Kilometre Array Organisation, Jodrell Bank Observatory, SK11 9DL, UK.

Nature

|February 26, 2016

まとめ

超高速電波 (FRB) は神秘的な宇宙信号ですこの研究はFRBを宿主銀河と結びつけ赤い偏移を測定し銀河間媒介と欠落しているバリオンの重要なデータを提供します

科学分野:

宇宙学
天体物理学
ラジオ天文学

背景:

急速無線爆発 (FRB) は,数ミリ秒間の超銀河間無線トランジエントです.
散乱の測定はFRBの重要な観測値ですが赤偏移の測定は困難でした
過去のFRB研究では宿主銀河の識別と赤道移転のデータがありませんでした

研究の目的:

正確に測定された赤偏移の急速な電波の発見を報告する
散乱の測定と赤偏移を使って離子化されたバリオンの宇宙密度を制限する
素早い電波の原型と性質を調査する

主な方法:

ラジオバースト (FRB) の検出
FRBの後に ~6日間の消える無線トランジタを特定する.
ホスト銀河の識別と赤偏移の測定 (z = 0.492 ± 0.008).

主要な成果:

銀河間媒質におけるイオン化されたバリオンの宇宙密度の直接測定 (ΩIGM = 4.9 ± 1.3%).
測定された ΩIGM は,ウィルキンソンマイクロウェーブアニゾトロピープローブ (WMAP) の予測と一致し,すべての"欠落したバリオン"を考慮します.
~6日間の無線トランジタは,少なくとも2つのクラスのFRBを示唆する短いガンマ線爆発の光と一致します.

結論:

この研究は,FRBを用いて銀河間媒体の電離バリオンの密度を初めて直接測定したものです.
この発見は宇宙のネットワークに重要な数のイオン化されたバリオンが存在することを支持している.
この結果はFRBの祖先モデルに異議を唱え起源の多様性を示唆している.

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