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Description
New proper motions have been derived from reductions of PDS microdensitometer scans of 17 Yerkes refractor plates spanning an epoch range of 88 years for 515 stars down to V~15.6 in the region of the globular cluster M5. Photographic photometry in B and V has been obtained for these stars from these scans and scans of six Yerkes reflector plates. The present proper motions have significantly improved precision compared to Cudworth [AJ, 84, 1866 (1979)]. Membership probabilities derived from the new proper motions are largely in agreement with those from Cudworth's study, but this paper includes nearly 200 additional stars, many of which are probable members. A color-magnitude diagram of probable members is presented and discussed, as well as comparisons to previous photometry. All but two of the previously known or suspected variables are found to be highly probable members. These proper motions have been used by Cudworth & Hanson [AJ, 105, 168 (1993)] to derive a large space velocity for M5, implying that it is a rich outer halo cluster on an eccentric orbit near perigalacticon. These motions will be used in a forthcoming paper to explore the internal dynamics of M5, including a derivation of the cluster distance by comparison of the proper motion and radial velocity dispersions.
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