With the ultimate aim of distinguishing between various models describing the formation of galaxy halos ( e.g .
radial or multi-phase collapse , random mergers ) , we have completed a spectroscopic study of the globular cluster system of M31 .
We present the results of deep , intermediate-resolution , fibre-optic spectroscopy of several hundred of the M31 globular clusters using the Wide Field Fibre Optic Spectrograph ( WYFFOS ) at the William Herschel Telescope in La Palma , Canary Islands .
These observations have yielded precise radial velocities ( \pm 12 km s ^ { -1 } ) and metallicities ( \pm 0.26 dex ) for over 200 members of the M31 globular cluster population out to a radius of 1.5 degrees from the galaxy center .
Many of these clusters have no previous published radial velocity or [ Fe/H ] estimates , and the remainder typically represent significant improvements over earlier determinations .
We present analyses of the spatial , kinematic and metal abundance properties of the M31 globular clusters .
We find that the abundance distribution of the cluster system is consistent with a bimodal distribution with peaks at { [ Fe / H ] } \sim - 1.4 and -0.5 .
The metal-rich clusters demonstrate a centrally concentrated spatial distribution with a high rotation amplitude , although this population does not appear significantly flattened and is consistent with a bulge population .
The metal-poor clusters tend to be less spatially concentrated and are also found to have a strong rotation signature .