  We study the radiative (E1 and M1) decays of P-wave quarkonia in a strong
magnetic field based on the Lagrangian of potential nonrelativistic QCD. To
investigate their properties, we implement a polarized wave function basis
justified in the Paschen-Back limit. In a magnetic field stronger than the
spin-orbit coupling, the wave functions of the P-wave quarkonia are drastically
deformed by the Hadronic Paschen-Back effect. Such deformation leads to the
anisotropy of the direction of decays from the P-wave quarkonia. The analytic
formulas for the radiative decay widths in the nonrelativistic limit are shown,
and the qualitative decay properties are discussed.
