We present the first kinematic analysis of the far outer halo globular cluster ( GC ) population in the Local Group galaxy M31 .
Our sample contains 53 objects with projected radii of \sim 20 - 130 kpc , of which 44 have no previous spectroscopic information .
GCs with projected radii \gtrsim~ { } 30 kpc are found to exhibit net rotation around the minor axis of M31 , in the same sense as the inner GCs , albeit with a smaller amplitude of 79±19 km/s .
The rotation-corrected velocity dispersion of the full halo GC sample is 106±12 km/s , which we observe to decrease with increasing projected radius .
We find compelling evidence for kinematic-coherence amongst GCs which project on top of halo substructure , including a clear signature of infall for GCs lying along the North-West stream .
Using the tracer mass estimator , we estimate the dynamical mass of M31 within 200 kpc to be M _ { M 31 } = ( 1.2 - 1.5 ) \pm 0.2 \times 10 ^ { 12 } M _ { \odot } .
This value is highly dependent on the chosen model and assumptions within .