赤い偏移9.51で拡大されたコンパクト銀河で,強い nebular 放射線
Hayley Williams1, Patrick L Kelly1, Wenlei Chen1
1Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55455, USA.
Science (New York, N.Y.)
|April 13, 2023
まとめ
ジェームズ・ウェブ宇宙望遠鏡 (JWST) を用いた初期の銀河観測は,赤道偏移 z = 9.51 でコンパクトで明るい銀河を明らかにした. この発見は再イオン化時代と 初期の銀河の進化について 新たな洞察を与えてくれます
科学分野:
- 宇宙学
- 銀河の進化
- 天体物理学
背景:
- 銀河間介質が初期の銀河からの紫外線でイオン化された再イオン化の時代は,観測的に弱いままです.
- 初期の銀河の薄弱さと 赤色移転による暗くなることは この重要な宇宙時代の観測を複雑にします
研究 の 目的:
- JWSTを用いて高赤偏移の銀河の性質を調査する.
- 宇宙の再イオン化における 初期の銀河の役割を制限するためです
主な方法:
- 遠くの銀河を観測するためにJWSTの画像を使用しました
- 銀河の静止フレームの光学スペクトルにおける nebular 放射線 (酸素,水素) を分析するためにJWSTスペクトロスコーピーを実行した.
主要な成果:
- 赤い偏移 z = 9.51 (ビッグバンから5億1000万年) の銀河を発見した.
- 銀河の半径は,赤偏差が低い (z ~ 6-8) 比較可能な銀河よりも著しく小さいことを決定した.
- この銀河の表面密度の高い恒星形成率を計算した.
結論:
- このコンパクトで明るく輝く銀河は 再イオン化の時代の貴重な探査機です
- 高い恒星形成密度は,そのような銀河が宇宙再イオン化に大きく貢献した可能性があることを示唆しています.
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