赤い偏移 6.2 で非常に拡大された星
Brian Welch1, Dan Coe2,3,4, Jose M Diego5
1Center for Astrophysical Sciences, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, MD, USA. bwelch7@jhu.edu.
Nature
|March 31, 2022
まとめ
天文学者は銀河団による重力レンズを用いて 遠くに拡大された星を発見しました この絶え間なく膨張する星は 初期の宇宙の星群を研究する ユニークな機会を与えてくれます
科学分野:
- 宇宙学と天体物理学
- 重力レンズ
- エクソプラネット研究
背景:
- 銀河団は強力な重力レンズとして 背景の物体を拡大します
- 強い重力レンズは 銀河を弧状に伸ばし 背景の光源の輝きを大幅に高めます
- 以前のレンズ状の星は赤偏移が低く,一時的なマイクロレンズ効果を示していた.
研究 の 目的:
- 遠くの恒星の発見と特徴を報告する
- 超大放大で初期の宇宙の星々を 調べるためでした
- 銀河団が 遠くの物体の観測を可能にする役割を 確認するためです
主な方法:
- 銀河団WHL0137-08による重力レンズを利用して背景の星を拡大した.
- 4つの独立したレンズモデルを使用して,拡大率を推定した.
- 照明の恒常性を評価するために,長期にわたる画像撮影とフォローアップ観察を行った.
主要な成果:
- ビッグバンから9億年後の6.2の赤偏移で 千倍に拡大した星を発見した
- 観測された恒常的な拡大と明るさ (ABマグニチュード27.2) は,一時的なマイクロレンズ星とは違います.
- 大量恒星 (>50太陽質量) と一致する - 10 ± 2 の絶対紫外線を計算した.
結論:
- この発見は重力レンズによる 初期の宇宙の 巨大な恒星の発見の可能性を示しています
- 拡大の持続的な性質は,詳細な研究のための安定したターゲットを提供します.
- ジェームズ・ウェブ宇宙望遠鏡によるさらなる観測により,スペクトルの分類と性質が確認される見込みである.
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