A New Virial Equilibrium for Galaxy Clusters Forming Finite Alignments

Abstract

Assuming only ellipticity it is argued that galaxy clusters can only be prolate, instead of spherical or oblate. With the help of this constraint, a lower limit for the cluster halo dark matter particle mass is derived depending on baryon particle mass. This takes the form of new ‘scaling relations' between ellipticity, dark matter fraction, dark matter particle mass and the Hubble constant h and the cosmological parameter k. The usual intra cluster virial equilibrium and the virial mass fraction constant are challenged when galaxy clusters form finite alignments.