Conformastatic disk-haloes in Einstein-Maxwell gravity
  We present a relativistic model describing a thin disk surrounded by a halo in presence of an electromagnetic field. The model is obtained by solving the Einstein-Maxwell equations on a particular conformastatic spacetime background and by using the distributional approach for the energy-momentum tensor. A class of solutions is obtained in which the gravitational and electromagnetic potentials are completely determined by a harmonic function only. A particular solution is given that is asymptotically flat and singularity-free, and satisfies all the energy conditions. 
Antonio C. Guti\'errez-Pi\~neres, Guillermo A. Gonz\'alez and Hernando   Quevedo
gr-qc math-ph math.MP