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arXiv · 1901.01961

Future constraints on the gravitational slip with the mass profiles of galaxy clusters

Lorenzo Pizzuti·Ippocratis D. Saltas·Santiago Casas·Luca Amendola·Andrea Biviano
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Abstract

The gravitational slip parameter is an important discriminator between large classes of gravity theories at cosmological and astrophysical scales. In this work we use a combination of simulated information of galaxy cluster mass profiles, inferred by Strong+Weak lensing analyses and by the study of the dynamics of the cluster member galaxies, to reconstruct the gravitational slip parameter $η$ and predict the accuracy with which it can be constrained with current and future galaxy cluster surveys. Performing a full-likelihood statistical analysis, we show that galaxy cluster observations can constrain $η$ down to the percent level already with a few tens of clusters. We discuss the significance of possible systematics, and show that the cluster masses and numbers of galaxy members used to reconstruct the dynamics mass profile have a mild effect on the predicted constraints.

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Lorenzo Pizzuti, Ippocratis D. Saltas, Santiago Casas, Luca Amendola, Andrea Biviano. 2019-01-07. Future constraints on the gravitational slip with the mass profiles of galaxy clusters. https://doi.org/10.1093/mnras%2Fstz825

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