Charged massive vector boson propagator in a constant magnetic field in arbitrary $\xi$-gauge obtained using the modified Fock-Schwinger method

We applied a recently published modified Fock-Schwinger (MFS) method to find the exact solution of the propagator equation for a charged vector boson in the presence of a constant magnetic field directly in the momentum space as a sum over Landau levels in arbitrary $\xi$-gauge. In contrast to the standard approaches for finding propagators, MFS method demonstrated several improvements in terms of computational complexity reduction and revealed simple internal structures in intermediate and final expressions, thus allowing to obtain new useful representations of the propagator.