  A semimicroscopical approach is applied to describe photoabsorption and
partial photonucleon reactions accompanied by the excitation of the giant
dipole resonance (GDR). The approach is based on the continuum-RPA (CRPA) with
a phenomenological description for the spreading effect. The phenomenological
isoscalar part of the nuclear mean field, momentum-independent Landau-Migdal
particle-hole interaction, and separable momentum-dependent forces are used as
input quantities for the CRPA calculations. The experimental photoabsorption
and partial $(n,\gamma)$-reaction cross sections in the vicinity of the GDR are
satisfactorily described for $^{89}$Y, $^{140}$Ce and $^{208}$Pb target nuclei.
The total direct-neutron-decay branching ratio for the GDR in $^{48}$Ca and
$^{208}$Pb is also evaluated.
