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We report on the structure of the nuclear star cluster in the innermost 0.16pc of the Galaxy as measured by the number density profile of late-type giants.Using laser guide star adaptive optics in conjunction with the integral fieldspectrograph, OSIRIS, at the Keck II telescope, we are able to differentiatebetween the older, late-type ($\sim$ 1 Gyr) stars, which are presumed to bedynamically relaxed, and the unrelaxed young ($\sim$ 6 Myr) population. Thisdistinction is crucial for testing models of stellar cusp formation in thevicinity of a black hole, as the models assume that the cusp stars are indynamical equilibrium in the black hole potential. Based on the late-type starsalone, the surface stellar number density profile, $\Sigma(R) \proptoR^{-\Gamma}$, is flat, with $\Gamma = -0.27\pm0.19$. Monte Carlo simulations ofthe possible de-projected volume density profile, n(r) $\propto r^{-\gamma}$,show that $\gamma$ is less than 1.0 at the 99.73 % confidence level. Theseresults are consistent with the nuclear star cluster having no cusp, with acore profile that is significantly flatter than predicted by most cuspformation theories, and even allows for the presence of a central hole in thestellar distribution. Of the possible dynamical interactions that can lead tothe depletion of the red giants observable in this survey -- stellarcollisions, mass segregation from stellar remnants, or a recent merger event --mass segregation is the only one that can be ruled out as the dominantdepletion mechanism. The lack of a stellar cusp around a supermassive blackhole would have important implications for black hole growth models andinferences on the presence of a black hole based upon stellar distributions.

High angular resolution integral-field spectroscopy of the Galaxy's nuclear cluster: a missing stellar cusp?