We constrain the chameleon screening mechanism in galaxy clusters, essentially obtaining limits on the coupling strength $\beta$ and the asymptotic value of the field ${\varphi }_{\infty }$. For this purpose, we utilized a collection of the nine relaxed galaxy clusters within the X-COP compilation in the redshift range of $z\le 0.1$. We implement the formalism assuming a Navarro-Frenk-White mass profile for the dark matter density and study the degeneracy present between the mass $M_{500}$ and the chameleon coupling with a high degree of improvement in the constraints for excluded parameter space. We recast our constrain to an upper limit on the scalaron field in $f(R)$ subclass of models of $|f_{R0}|\le 9.2\times {10}^{-6}$, using all the nine clusters and $|f_{R0}|\le 1.2\times {10}^{-5}$ using only five clusters with Weak lensing priors taken into account, at a 95% confidence level. These bounds are consistent with existing limits in the literature and tighter than the constraints obtained with the same method by previous studies.

• Received 13 March 2023
• Accepted 14 July 2023

DOI:https://doi.org/10.1103/PhysRevD.108.044007