Constraining $f(R)$ Gravity Theory Using Weak Lensing Peak Statistics from the Canada-France-Hawaii-Telescope Lensing Survey

TL;DR

This study uses weak lensing peak statistics from the CFHTLens survey to place observational constraints on the Hu-Sawicki $f(R)$ gravity model, providing tighter bounds than previous methods.

Contribution

It presents the first constraints on the Hu-Sawicki $f(R)$ gravity model using weak lensing peak statistics from CFHTLens data, avoiding reliance on baryonic observable calibrations.

Findings

95% CL limit: $oxed{ ext{log}_{10}|f_{R0}| < -4.82}$ with WMAP9 priors.

95% CL limit: $oxed{ ext{log}_{10}|f_{R0}| < -5.16}$ with Planck15 priors.

Weak lensing peak analysis yields competitive constraints on modified gravity models.

Abstract

In this Letter, we report the observational constraints on the Hu-Sawicki $f(R)$ theory derived from weak lensing peak abundances, which are closely related to the mass function of massive halos. In comparison with studies using optical or x-ray clusters of galaxies, weak lensing peak analyses have the advantages of not relying on mass-baryonic observable calibrations. With observations from the Canada-France-Hawaii-Telescope Lensing Survey, our peak analyses give rise to a tight constraint on the model parameter $|f_{R0}|$ for $n=1$. The $95\%$ CL limit is $\log_{10}|f_{R0}| < -4.82$ given WMAP9 priors on $(\Omega_{\rm m}, A_{\rm s})$. With Planck15 priors, the corresponding result is $\log_{10}|f_{R0}| < -5.16$.