Abstract:
On the base of the matrix $10$-dimensional formalism, behavior of a vector particle with a quadrupole moment is studied in presence
of external uniform magnetic field. Three series of the energy levels related to bound states of the particle are found. To
assign them physical sense for all values of the main quantum number $n = 0,1,2,\dots$ one must impose special restrictions on
quadrupole moment — they are formulated explicitly. Also, the problem of a neutral vector particle with quadrupole moment in
presence of magnetic field is studied. At this, solutions of three types are constructed in terms of Bessel functions, in each case
the influence of the quadrupole moment consists in presence of a scale factor $\mu$ in the argument $x=\mu r$ of the functions, which
depends on the quadrupole moment parameter and magnitude of the uniform magnetic field.
Keywords:vector particle, quadrupole moment, magnetic field, Duffin–Kemmer formalism, separation of the variables, exact solutions.