On 15-component theory of a charged spin-1 particle with polarizability   in Coulomb and Dirac monopole fields
  The problem of a spin 1 charged particle with electromagnetic polarizability, obeying a generalized 15-component quantum mechanical equation, is investigated in presence of the external Coulomb potential. With the use of the Wigner's functions techniques, separation of variables in the spherical tetrad basis is done and the 15-component radial system is given. It is shown that there exists a class of quantum states for which the additional characteristics, polarizability, does not manifest itself anyhow; at this the energy spectrum of the system coincides with the known spectrum of the scalar particle. For j=0 states, a 2-order differential equation is derived, it contains an additional potential term 1/r^{4}. In analogous approach wave functions the generalized particle are examined in presence of external Dirac monopole field. It is shown that there exists one special state with minimal conserved quantum number j_{min}. It this solution, first, the polarizability does not exhibits itself. Analysis of the usual vector particle in external Coulomb potential is given. It is shown that at j=0 some bound states will arise. The corresponding energy spectrum is found. 
V.M.Red'kov, N.G.Tokarevskaya, V.V.Kisel