A detection of baryon acoustic oscillations from the distribution of galaxy clusters

TL;DR

This paper detects baryon acoustic oscillations in galaxy cluster distribution, providing measurements consistent with Planck 2015 cosmology and exploring anisotropic BAO features.

Contribution

First detection of BAO in galaxy cluster distribution with significance, using a large sample and mass weighting, and analysis of anisotropic BAO signals.

Findings

BAO peak detected at 3.7 sigma significance

Measured distance scale consistent with Planck 2015 cosmology

Observed higher amplitude in high-mass cluster sub-sample

Abstract

We calculate the correlation function of 79,091 galaxy clusters in the redshift region of $z \leq 0.5$ selected from the WH15 cluster catalog. With a weight of cluster mass, a significant baryon acoustic oscillation (BAO) peak is detected on the correlation function with a significance of $3.7 \sigma$. By fitting the correlation function with a $\Lambda$CDM model curve, we find $D_v(z = 0.331) r_d^{fid}/r_d = 1261.5 \pm 48$~Mpc which is consistent with the Planck 2015 cosmology. We find that the correlation function of the higher mass sub-sample shows a higher amplitude at small scales of $r < 80~h^{-1}{\rm Mpc}$, which is consistent with our previous result. The 2D correlation function of this large sample of galaxy clusters shows a faint BAO ring with a significance of $1.8\sigma$, from which we find that the distance scale parameters on directions across and along the line-of-sight are $\alpha_{\sigma} = 1.02 \pm 0.06$ and $\alpha_{\pi} = 0.94 \pm 0.10$, respectively.