初期の宇宙におけるブラックホールの成長は自己調節され,視野からほとんど隠されている

Ezequiel Treister¹, Kevin Schawinski, Marta Volonteri

¹Institute for Astronomy, 2680 Woodlawn Drive, University of Hawaii, Honolulu, Hawaii 96822, USA. treister@ifa.hawaii.edu

Nature

|June 17, 2011

まとめ

銀河における初期の巨大なブラックホールの成長は,著しく過小評価されていた. これらのブラックホールは宿主銀河と共に成長したが,ガスと塵によって遮られ,初期の宇宙の再イオン化への影響を制限した.

科学分野:

コスモロジー・コスモロジーとは
天体物理学天体物理学
銀河の進化銀河の進化銀河の進化

背景:

ブラックホールを含む最初の巨大な天体の形成は,初期の宇宙を理解するために極めて重要です.
これらの初期のオブジェクトの直接観測は困難であり,ブラックホール形成チャネルに関する私たちの理解を制限しています.
初期の宇宙で観測された超大質量ブラックホールは,急速な成長による初期条件に限られた制約を与えます.

研究の目的:

銀河のブラックホールの成長を赤道移転 z = 6-8 (0.95-0.7億年後のビッグバン) で測定する.
最古の宇宙時代からブラックホールとその宿主銀河の共同進化を理解するために.
初期のブラックホールの成長が宇宙の再イオン化に与える貢献を評価する.

主な方法:

ブラックホールの成長を測定するために,最適に積み重ねられたアーカイブX線観測を用いた.
ガスと塵の遮蔽を貫通するためのX線放射を分析した.
赤道偏移 z = 6-8 の銀河にフォーカスし,初期の宇宙に対応しています.

主要な成果:

ブラックホールは,最古の宇宙時代から宿主銀河と並行して成長しています.
これらの初期の時代において,最も活発に蓄積しているブラックホールは,ガスと塵によって大きく覆われている.
これらのブラックホールからの遮蔽された紫外線放射は,それらは宇宙の再イオン化に有意に寄与しなかったことを示唆しています.

結論:

ブラックホールの成長は,初期の段階から銀河の進化と密接に関連しています.
ブラックホールの大幅な成長は,初期の宇宙で発生し,遮蔽物質によって覆われた.
宇宙の再イオン化は,これらの初期の,遮蔽されたブラックホールの紫外線放射によって引き起こされたわけではない.

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