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We have identified seven ultraluminous X-ray sources (ULXs) which arecoincident with globular cluster candidates (GCs) associated with M87. ULXs inthe old GC environment represent a new population of ULXs, and ones likely tobe black holes. In this study we perform detailed X-ray spectroscopic followupto seven GC ULXs across a wealth of archival Chandra observations and long timebaseline of 16 years. This study brings the total known sample of GC ULXs to17. Two of these sources show variability in their X-ray luminosity of an orderof magnitude over many years, and one of these sources showsintra-observational variability on the scale of hours. While the X-ray spectraof the majority of globular cluster ULXs are best fit by single componentmodels, one of the sources studied in this paper is the second GC ULX to bebest fit by a two component model. We compare this new sample of GC ULXs to thepreviously studied sample, and compare the X-ray and optical propertiescounterparts across the samples. We find that the clusters that host ULXs inM87 have metallicities from g-z=1.01 to g-z=1.70. The best-fit power-lawindices of the X-ray spectra range from Gamma=1.37-2.21, and the best fit innerblack-body disk temperatures range from kT=0.56-1.90 keV.

X-Ray Spectroscopy of Newly Identified ULXs Associated With M87's Globular Cluster Population