Evidence of Halo Assembly Bias in Massive Clusters

Hironao Miyatake, Surhud More, Masahiro Takada, David N. Spergel, Rachel Mandelbaum, Eli S. Rykoff, Eduardo Rozo

Research output: Contribution to journalArticlepeer-review

103 Scopus citations


We present significant evidence of halo assembly bias for SDSS redMaPPer galaxy clusters in the redshift range [0.1, 0.33]. By dividing the 8,648 clusters into two subsamples based on the average member galaxy separation from the cluster center, we first show that the two subsamples have very similar halo mass of M200m≃1.9×1014 h-1M based on the weak lensing signals at small radii R 10 h-1Mpc. However, their halo bias inferred from both the large-scale weak lensing and the projected autocorrelation functions differs by a factor of ∼1.5, which is a signature of assembly bias. The same bias hypothesis for the two subsamples is excluded at 2.5σ in the weak lensing and 4.4σ in the autocorrelation data, respectively. This result could bring a significant impact on both galaxy evolution and precision cosmology.

Original languageEnglish (US)
Article number041301
JournalPhysical review letters
Issue number4
StatePublished - Jan 25 2016

All Science Journal Classification (ASJC) codes

  • General Physics and Astronomy


Dive into the research topics of 'Evidence of Halo Assembly Bias in Massive Clusters'. Together they form a unique fingerprint.

Cite this