The proposal aims at providing the needed support for the face-to-face meetings of the Steering Committee of our XMM Heritage Cluster Project.

The Heritage program for the ESA’s X-ray satellite XMM-Newton has been activated for the first time in the last Announcement of Opportunity. It has registered a large response from the community, with an oversubscription factor of 10, and has assigned about 3 Msec of XMM exposure time to two only projects, one led by our group. The X-ray observations will start in Spring 2018 and will be executed in the next 3 years.

Our project is focused on the ultimate products of structure formation in mass and time:
a large, unbiased, signal-to-noise limited sample of 118 galaxy clusters detected by Planck via their Sunyaev-Zel’dovich effect. Completing the high-fidelity XMM coverage of this sample has extraordinary legacy value. We will (i) obtain an accurate vision of the statistical properties of the local cluster population, and in the highest mass regime; (ii) uncover the provenance of non-gravitational heating; (iii) measure how their gas is shaped by the collapse into dark matter haloes and the mergers that built today’s clusters; (iv) resolve the major uncertainties in mass determinations that limit cosmological inferences; (v) build the foundation for cluster science with next-generation surveys.

The Steering Committee, including the two PIs and 10 other co-Is of the XMM Heritage proposal from 10 institutes of 5 different countries (France, Germany, Italy, UK and US),
will coordinate and promote all the activities of this unique, very compelling program.