We present an analytic approach to lift the mass-anisotropy degeneracy in clusters of galaxies by utilizing the line-of-sight velocity dispersion of clustered galaxies jointly with weak lensing-inferred masses .
More specifically , we solve the spherical Jeans equation by assuming a simple relation between the line-of-sight velocity dispersion and the radial velocity dispersion and recast the Jeans equation as a Bernoulli differential equation which has a well-known analytic solution .
We first test our method in cosmological N-body simulations and then derive the anisotropy profiles for 35 archival data galaxy clusters with an average redshift of \langle z _ { c } \rangle = 0.25 .
The resulting profiles yield a weighted average global value of \langle \beta ( 0.2 \leq R / R _ { 200 } \leq 1 ) \rangle = 0.35 \pm 0.28 ( stat ) \pm 0.15 ( sys ) .
This indicates that clustered galaxies tend to globally fall on radially anisotropic orbits .
We note that this is the first attempt to derive velocity anisotropy profiles for a cluster sample of this size utilizing joint dynamical and weak lensing data .