恒星形成における磁気超臨界度への初期の移行
T-C Ching1, D Li2,3,4, C Heiles5
1National Astronomical Observatories, Chinese Academy of Sciences, Beijing, China.
Nature
|January 6, 2022
まとめ
研究者は,H I 狭い自己吸収 (HINSA) を使用して,星のないコアに磁場を検出しました. この発見は 磁場強度が 予想より早く 減少することを示唆しています
科学分野:
- 天体物理学
- 星間媒体の物理
- 星の形成
背景:
- 磁場は恒星間媒体の進化と恒星形成に不可欠です
- 恒星間磁場の直接的な測定は,特に冷たい分子ガスでは,シーマン探査機のデータが稀であるため制限されています.
研究 の 目的:
- プレステラー・コアL1544の磁場強さを検出し,定量化する.
- 異なるガス相 (原子と分子) にわたる磁場の一貫性を調査する.
主な方法:
- H I 狭い自己吸収 (HINSA) を利用して,ジーマン効果を介して磁場強さを測定した.
- クワザールH I吸収,H I放出,OH放出からの既存のジーマン測定値とHINSAデータを組み合わせた.
主要な成果:
- L1544のコアで +3.8 ± 0.3マイクロガウスの磁場を検出しました.
- 原子冷中性介質 (CNM) から分子封筒に及ぶ一貫した磁場を明らかにした.
- HINSAによって追跡された分子封筒は 磁界の強さで 磁界の強さで 磁界の強さで 磁界の強さで 磁界の強さで 磁界の強さで
結論:
- 星の形成に不可欠な質量に対する磁気流の減少は,CNMから分子ガスへの移行の間に,これまで考えられていたよりも早く起こります.
- これは 磁気的臨界外層から 恒星形成の核が形成される 伝統的なモデルに 異議を唱えます
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