Deriving galaxy cluster velocity anisotropy profiles from a joint
  analysis of dynamical and weak lensing data
  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
that 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 $\langle \beta (0.2\leqslant R/{R}_{200}\leqslant 1)\rangle =0.35\pm
0.28$ (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
