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Using flow models based on axisymmetric general relativisticmagnetohydrodynamics (GRMHD) simulations, we construct radiative models for sgrA*. Spectral energy distributions that include the effects of thermalsynchrotron emission and absorption, and Compton scattering, are calculatedusing a Monte Carlo technique. Images are calculated using a ray-tracingscheme. All models are scaled so that the 230 GHz flux density is 3.4 Jy. Thekey model parameters are the dimensionless black hole spin a*, the inclinationi, and the ion-to-electron temperature ratio Ti/Te. We find that: (1) modelswith Ti/Te=1 are inconsistent with the observed submillimeter spectral slope;(2) the X-ray flux is a strongly increasing function of a*; (3) the X-ray fluxis a strongly increasing function of i; (4) 230 GHz image size is a complicatedfunction of i, a*, and Ti/Te, but the Ti/Te = 10 models are generally large andat most marginally consistent with the 230 GHz VLBI data; (5) for models withTi/Te=10 and i=85 deg the event horizon is cloaked behind a synchrotronphotosphere at 230 GHz and will not be seen by VLBI, but these modelsoverproduce NIR and X-ray flux; (6) in all models whose SEDs are consistentwith observations the event horizon is uncloaked at 230 GHz; (7) the modelsthat are most consistent with the observations have a* \sim 0.9. We finish witha discussion of the limitations of our model and prospects for futureimprovements.

Radiative Models of Sgr A* from GRMHD Simulations