銀河外の硬いX線背景を解明する
Nature
|April 13, 2000
まとめ
研究者達は,何十年にもわたって宇宙の謎であった,硬いX線背景の源を特定した. ディープ・チャンドラによる観測により,これらの源が背景と一致していることが明らかになった.
科学分野:
- 宇宙X線天文学の宇宙X線
- 天体物理学 天体物理学
- 高エネルギー天体物理学
背景:
- 硬いX線背景 (2-10 keV) の起源は,35年以上にわたって解明されていないままです.
- 柔らかいX線背景源 (主にクエザール) が特定されているが,そのスペクトルのエネルギー分布は全体の背景スペクトルと一致していない.
研究 の 目的:
- 硬いX線背景の起源の謎を調査し解明する.
- 硬いX線背景に寄与する源を特定し,その性質を分析する.
主な方法:
- 深いX線調査のために,チャンドラ衛星を利用した.
- 検出された硬質X線源のスペクトルエネルギー分布を分析した.
主要な成果:
- 検出されたハードX線源は,ハードX線背景の少なくとも75%を占めています.
- これらの源の平均スペクトルエネルギー分布は,背景スペクトルとほぼ一致しています.
- 特定された源は,明るい銀河の核,光学的に薄い物体,潜在的に活発な銀河の核,または高赤道移転クワザールと関連しています.
結論:
- この研究は,ハードX線背景の長年の謎を大幅に解明しています.
- 特定された情報源は,観測されたハードX線背景スペクトルの強力な説明を提供します.
- この発見は,活発な銀河核,おそらく遮蔽された,または遠いクエーサールからの重要な貢献を示唆しています.
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