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arXiv · 2412.09134

Modified gravity in galaxy clusters: Joint analysis of Hydrostatics and Caustics

Minahil Adil Butt·Sandeep Haridasu·Yacer Boumechta·Francesco Benetti·Lorenzo Pizzuti·Carlo Baccigalupi·Andrea Lapi
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Abstract

We present a comprehensive joint analysis of two distinct methodologies for measuring the mass of galaxy clusters: hydrostatic measurements and caustic techniques. We show that by including cluster-specific assumptions obtained from hydrostatic measurements in the caustic method, the potential mass bias between these approaches can be significantly reduced. Applying this approach to two well-observed massive galaxy clusters A2029 and A2142. We find no discernible mass bias, affirming the method's validity. We then extend the analysis to modified gravity models and draw a similar conclusion when applying our approach. Specifically, our implementation allows us to investigate Chameleon and Vainshtein screening mechanisms, tightening the posteriors and enhancing our understanding of these modified gravity scenarios.

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Minahil Adil Butt, Sandeep Haridasu, Yacer Boumechta, Francesco Benetti, Lorenzo Pizzuti, Carlo Baccigalupi, Andrea Lapi. 2024-12-12. Modified gravity in galaxy clusters: Joint analysis of Hydrostatics and Caustics. https://arxiv.org/abs/2412.09134

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