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We begin by presenting the analysis of a set of deep B- and V-band images ofthe central density cusp of the globular cluster M30 (NGC 7099), taken with theFaint Object Camera aboard the Hubble Space Telescope. These images are thefirst to resolve lower-mass main-sequence stars in the cluster's central 10''.From the positions of individual stars, we measure an improved position for thecluster center; this new position is 2.6'' from the previously known position.We find no evidence of a ``flat'', constant-surface-density core; however, thedata do not rule out the presence of a core of radius up to 1.9'' (95%confidence level). We measure a logarithmic cusp slope (d \log \sigma / d \logr$) of -0.76 +- 0.07 (1-sigma) for stars with masses between 0.69 and 0.76\Msun, and -0.82 +- 0.11 for stars with masses between 0.57 and 0.69 \Msun. Wealso compare the overall mass function (MF) of the cluster cusp with the MF ofa field at r = 4.6' (near the cluster half-mass radius). The observed degree ofmass segregation is well matched by the predictions of an isotropic, multimassKing model. We then use the Jeans equation to compare the structure of M30 withthat of M15, another cusped cluster, using data from this and a previous paper.We find that M30 is very close to achieving equipartition of energy betweenstellar species, at least over the observed range in mass and radius, while M15is not. This difference may be a result of the longer relaxation time in theobserved field in M15. The data also suggest that the degree of masssegregation within the two cluster cusps is smaller than one would expect fromthe measurements at larger radius. If so, this phenomenon might be the resultof gravothermal oscillations, of centrally-concentrated populations ofbinaries, or of a ~10^3 \Msun black hole in one or more clusters

Mass Segregation and Equipartition of Energy in Two Globular Clusters with Central Density Cusps.