最も若い恒星からの流出は主に分子です.
T P Ray1,2, M J McCaughrean3, A Caratti O Garatti4
1Dublin Institute for Advanced Studies, Dublin, Ireland. tr@cp.dias.ie.
Nature
|August 24, 2023
まとめ
若い星は強力なジェットで物質を放出します ジェームズ・ウェブ宇宙望遠鏡の観測により,これらのジェットは主に原子やイオンではなく,熱い分子で構成されていることが明らかになりました.
科学分野:
- * 天体物理学
- * 星の形成
- * 惑星科学
背景:
- * 恒星と惑星の形成は 超音速ジェットによる物質の蓄積と放出の両方を含みます
- *若い原星は最も強力なジェットを示しますが,塵によって遮られ,観測を制限します.
- * 熱い,原子,イオン化,分子構成要素は ジェットの骨格を形成し,大部分は観察されないままです.
研究 の 目的:
- * 青い原始星のジェット,特にそれらの熱い構成要素の組成を調査する.
- * 星系外流で観測される"緑色のぼんやり"の起源を説明するために
- * 赤外線観測を用いてジェット進化の初期段階を調査する.
主な方法:
- * ジェームズ・ウェブ宇宙望遠鏡 (JWST) を用いた近赤外線観測
- * ハービグ・ハロ211の標的観測,若い原星からの流出.
- * 熱い分子,原子,イオン化されたガスからの放射の分析.
主要な成果:
- * 熱い分子からの大量放出がヘルビグ・ハロ211の流出で検出された.
- * 緑色のぼやけは これらの熱い分子からの放射として説明されます.
- * ジェット脊椎はほとんど純粋に分子で,最小限の原子またはイオン化放射があることが判明しました.
- * 流出は,より進化したジェットと比較して,より遅い伝播を示します.
結論:
- * 青い星体ジェットの骨格は主に分子です.
- *JWSTの赤外線能力は 星系外流の隠れた熱い成分を観測するのに 極めて重要です
- * この研究は,ジェット形成と進化の初期段階に関する新しい洞察を提供します.
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