A discrete chemo-dynamical model of M87's globular clusters: Kinematics
  extending to ~ 400 kpc
  We study the mass distribution and kinematics of the giant elliptical galaxy
M87 (NGC 4486) using discrete chemo-dynamical, axisymmetric Jeans equation
modelling. Our catalogue comprises 894 globular clusters (GCs) extending to a
projected radius of $\sim 430$ kpc with line-of-sight velocities and colours,
and Multi Unit Spectroscopic Explorer (MUSE) integral field unit data within
the central $2.4$ kpc of the main galaxy. The gravitational potential for our
models is a combination of a luminous matter potential with a varying
mass-to-light ratio for the main galaxy, a supermassive black hole and a dark
matter (DM) potential with a cusped or cored DM halo. The best-fitting models
with either a cusped or a cored DM halo show no significant differences and
both are acceptable. We obtain a total mass of $(2.16 \pm 0.38) \times 10^{13}
M_{\odot}$ within $\sim$ 400 kpc. By including the stellar mass-to-light ratio
gradient, the DM fraction increases from $\sim$ 26 percent (with no gradient)
to $\sim$ 73 percent within $1\,R_e^{\rm maj}$ (major axis of half-light
isophote, 14.2 kpc), and from $\sim$ 84 percent to $\sim$ 94 percent within
$5\,R_e^{\rm maj}$ (71.2 kpc). Red GCs have moderate rotation with $V_{\rm
max}/\sigma \sim$ 0.4, and blue GCs have weak rotation with $V_{\rm max}/\sigma
\sim$ 0.1. Red GCs have tangential velocity dispersion anisotropy, while blue
GCs are consistent with being nearly isotropic. Our results suggest that red
GCs are more likely to be born in-situ, while blue GCs are more likely to be
accreted.
