Morgan Le Delliou
Instituto de Física Teórica, Universidade Estadual de São Paulo, Brazil
In this talk we investigate the possibility of detection of Dark matter-Dark energy interaction. In particular, we try to detect the effects from such interaction in the balance of general clusters and for that purpose, we evaluate the departure from virial equilibrium of unbalanced clusters. We extend the use, from previous works, of the Layzer-Irvine equation for dynamical virial evolution of a simple model of interacting dark sector, with weak lensing and X-ray observations giving respectively the mass profiles and the intracluster gas temperatures. Selecting a set of clusters, we generate measurements, through a Monte Carlo method, of observed virial ratios, interaction strength, rest virial ratio and departure from equilibrium factors. We found a compounded interaction strength for the set of clusters of $-1.61^+2.23_-16.34$, compatible with no interaction, but a compounded rest virial ratio of $-0.78 ± 0.13$, which would entail a 2sigma detection. We confirm quantitatively that clusters of galaxies are out of equilibrium but further investigation is needed to constrain a possible interaction in the dark sector.
2015 July 20, 11:00
Faculdade de Ciências da Universidade de Lisboa (C6.2.51)
Campo Grande, 1749-016 Lisboa