New observational constraints on interacting dark energy using galaxy
  clusters virial equilibrium states
  As the dark sector remains unknown in composition and interaction between
dark energy and dark matter stand out as natural, observations of galaxy
clusters out of equilibrium abound, opening a promising window on these
questions. We continue here the exploration of dark sector interaction
detection via clusters virial equilibrium state for all clusters
configurations. The dynamics of clusters is evaluated with the Layzer-Irvine
equation, a simple model of an interacting dark sector and some simplifying
assumptions to obtain the time-dependent part of the virial dynamics. The
clusters' data are concentrated in optical weak lensing and X-ray observations
that evaluate, respectively, the clusters' mass profiles and temperatures. The
global inconsistency of available X-ray data led us to constitute `gold'
cluster samples. Through a Bayesian analysis, they are processed to obtain
consistent interaction detected up to 3$\sigma$, in compounded interaction
strength for 11 clusters at $-0.027 \pm 0.009$ that translate in compounded
universal equilibrium virial ratio of $-0.61^{+0.04}_{-0.03}$. The level of
detection and inconsistency of X-ray data call for caution, although future
instruments promise a clearer detection soon.
