Dark matter distribution in X-ray luminous galaxy clusters with Emergent Gravity

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We present the radial distribution of the dark matter in two massive, X-ray luminous galaxy clusters, Abell~2142 and Abell~2319, and compare it with the quantity predicted as apparent manifestation of the baryonic mass in the context of the "Emergent Gravity" scenario, recently suggested from Verlinde (2016).

• Thanks to the observational strategy of the \xmm\ Cluster Outskirt Programme (X-COP), using the X-ray emission mapped with \xmm\ and the SZ signal in the Planck survey, we recover the gas density, temperature and thermal pressure profiles up to $\sim R_{200}$, allowing to constrain at unprecedented level the total mass through the hydrostatic equilibrium equation.
• We show that, also including systematic uncertainties related to the X-ray based mass modelling, the apparent &#34;dark&#34; matter shows a radial profile that has a shape different from the traditional dark matter distribution, with larger discrepancies (by a factor 2--3) in the inner ($r<200$ kpc) cluster's regions and a remarkable agreement only across $R_{500}$.