  A quantum mechanical coupled-channel scattering calculation on the
Stark-Werner potential energy surface is used to study the F + H2(v=0; j=0,1,2)
---> H + HF(v', j') reaction at collision energies of 1.84, 2.74, and 3.42
kcal/mol. The dependence of the vibrationally and rotationally resolved
differential cross sections on the product vibrational levels v'=0, 1, 2, and 3
as well as on the reactant and product rotational levels is analyzed. The
HF(v'=3) center-of-mass forward scattering peak is shown to be caused by the
superposition of two effects, namely, the absence of the HF(v'=3; j') products
with large j' values due to energy constraints and the growth of the
rotationally resolved HF(v', j') forward scattering peak with small j' values
as v' increases.
