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The proper motions of stars in the outskirts of globular clusters are used toestimate cluster velocity dispersion profiles as far as possible within theirtidal radii. We use individual color-magnitude diagrams to select highprobability cluster stars for 25 metal-poor globular clusters within 20 kpc ofthe sun, 19 of which have substantial numbers of stars at large radii. Of the19, 11 clusters have a falling velocity dispersion in the 3-6 half mass radiirange, 6 are flat, and 2 plausibly have a rising velocity dispersion. Theprofiles are all in the range expected from simulated clusters started at highredshift in a zoom-in cosmological simulation. The 11 clusters with fallingvelocity dispersion profiles are consistent with no dark matter above theGalactic background. The 6 clusters with approximately flat velocity dispersionprofiles could have local dark matter, but are ambiguous. The 2 clusters withrising velocity dispersion profiles are consistent with a remnant local darkmatter halo, but need membership confirmation and detailed orbital modeling tofurther test these preliminary results.

Testing for Dark Matter in the Outskirts of Globular Clusters