Ground state of a confined Yukawa plasma
  The ground state of an externally confined one-component Yukawa plasma is derived analytically. In particular, the radial density profile is computed. The results agree very well with computer simulations on three-dimensional spherical Coulomb crystals. We conclude in presenting an exact equation for the density distribution for a confinement potential of arbitrary geometry. 
C. Henning, H. Baumgartner, A. Piel, P. Ludwig, V. Golubnichiy, M.   Bonitz, D. Block