銀河系 の ハロー に は 大量 の ブラックホール が ない
Przemek Mróz1, Andrzej Udalski2, Michał K Szymański2
1Astronomical Observatory, University of Warsaw, Warsaw, Poland. pmroz@astrouw.edu.pl.
Nature
|June 24, 2024
まとめ
初期ブラックホールは ダークマターの候補です 20年間のマイクロレンズ調査は これらの物体の証拠を 見つけられず ダークマターの主要な構成要素として 排除されました
科学分野:
- 天体物理学
- 宇宙学
- 重力波天文学
背景:
- 重力波探知器は 銀河系観測と矛盾する 巨大なブラックホールを明らかにしています
- これらのブラックホールの起源は議論されており,原始ブラックホール (PBH) が可能性として提案されている.
- PBHはダークマターの大部分を占め 銀河のハロに存在するなら 合併率を説明できるでしょう
研究 の 目的:
- PBHsを示す長い時間スケールの重力マイクロレンズイベントを検索します.
- 特定の質量範囲で PBH の豊富さを制限する.
主な方法:
- 大マゲラン雲の8000万個の恒星から 20年間の光線曲線データを分析しました
- 1年以上のマイクロレンズイベントを検索した.
主要な成果:
- 1年以上のマイクロレンズ発生は検出されなかった.
- 観測された短いイベントは既知の恒星集団に起因する.
- 1.8×10-4Mと6.3Mの間のコンパクトな物体は,ダークマターの1%以上を構成することはできません.
- 1.3×10-5Mと860Mの間のコンパクトな物体は,ダークマターの10%以上を構成することはできません.
結論:
- この研究は,研究された質量範囲におけるPBHを暗黒物質の重要な成分として排除しています.
- PBHは観測された重力波現象と重要なダークマターの分子を同時に説明することはできません.
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