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Super-resolution Imaging of the Bacterial Division Machinery
Published on: January 21, 2013
2dF Galaxy Redshift Surveyにおけるクラスタリングによる宇宙学的質量密度の測定である
J A Peacock1, S Cole, P Norberg
1Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK. jap@roe.ac.uk
Nature
|March 10, 2001
まとめ
銀河超群は銀河の崩壊を引き起こし,大規模な構造に影響を与えます. この研究では,2dF調査を用いて銀河のクラスタリングを正確に測定し,重要な宇宙学的パラメータ (β) を得ました.
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
- 銀河の形成 銀河の形成
背景:
- 大規模構造の形成は,初期密度の変動の重力不安定に起因する.
- スーパークラスターの形成は銀河の崩壊を誘導し,観測可能な速度アニソトロピーを引き起こすると予測されています.
研究 の 目的:
- 銀河団のクラスタリングを正確に測定し,重力不安定性仮説をテストするために.
- 宇宙学的パラメータβ (Ω^0.6/b) を決定し,宇宙の密度を推論する.
主な方法:
- 2dF Galaxy Redshift Surveyからの14万1,000以上の銀河からの赤道移転データを活用しました.
- 銀河の空間群集におけるアニソトロピーを検出するために,衰退速度パターンを分析した.
主要な成果:
- パラメータβ = Ω^0.6/b = 0.43 ± 0.07.0を決定しました.
- 光質と総質量クラスタリングのバイアス (b) を定量化しました.
結論:
- 結果は, Ω が約 0.3.3 の低密度宇宙を好む.
- 発見は,宇宙構造形成の重力不安定モデルを支持する.
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