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Two new families of exact solutions to the Einstein equations for aconformastatic spacetime with axial symmetry are presented which describe thindisks of dust immersed in a spheroidal halo. The solutions are obtained byexpressing the metric function in terms of an auxiliary function whichsatisfies the Laplace equation, a characteristic property of the conformastaticspacetimes. The first family of solutions is obtained from the displacement,cut and reflexion method, which introduces a discontinuity in the first$z$-derivate of the metric tensor across the plane of the disk. The secondfamily of solutions is obtained by using the oblate spheroidal coordinatesbecause they adapt to the shape of the source and introduce naturally a cuttingradius for the disk. The energy densities of the disk and the halo areeverywhere positive and well behaved and their energy-momentum tensor agreeswith all the energy conditions. Some particular solutions for the energydensity of the disk and the halo are presented and the rotational curves areobtained by solving the geodesic equation for a particle that moves in circularorbits in the plane of the disk.

Static Thin Disks with Haloes as Sources of Conformastatic Spacetimes