def targetSurfacemass(self,R,log=False):
         """
         NAME:

            targetSurfacemass

         PURPOSE:

            evaluate the target surface mass at R

         INPUT:

            R - radius at which to evaluate (can be Quantity)

            log - if True, return the log (default: False)

         OUTPUT:

            Sigma(R)

         HISTORY:

            2010-03-28 - Written - Bovy (NYU)

         """
         return self._surfaceSigmaProfile.surfacemass(R,log=log)