  An expression for the partial frequency redistribution (PRD) matrix for line
scattering in a two-term atom, which includes the J-state interference between
its fine structure line components is derived. The influence of collisions
(both elastic and inelastic) and an external magnetic field on the scattering
process is taken into account. The lower term is assumed to be unpolarized and
infinitely sharp. The linear Zeeman regime in which the Zeeman splitting is
much smaller than the fine structure splitting is considered. The inelastic
collision rates between the different levels are included in our treatment. We
account for the depolarization caused by the collisions coupling the fine
structure states of the upper term, but neglect the polarization transfer
between the fine structure states. When the fine structure splitting goes to
zero, we recover the redistribution matrix that represents the scattering on a
two-level atom (which exhibits only m-state interference --- namely the Hanle
effect). The way in which the multipolar index of the scattering atom enters
into the expression for the redistribution matrix through the collisional
branching ratios is discussed. The properties of the redistribution matrix are
explored for a single scattering process for an L=0 to 1 to 0 scattering
transition with S=1/2 (a hypothetical doublet centered at 5000 A and 5001 A).
Further, a method for solving the Hanle radiative transfer equation for a
two-term atom in the presence of collisions, PRD, and J-state interference is
developed. The Stokes profiles emerging from an isothermal constant property
medium are computed.
