  The E1 strength functions and radiative capture cross sections for several
compound Sn isotopes, including unstable 132S n and 150S n, have been
calculated using the self-consistent microscopic theory. In addition to the
standard RPA or QRPA approaches, the method includes the quasiparticle-phonon
coupling and the single-particle continuum. The results obtained show that the
phonon contribution is very noticeable for the pygmy-dipole resonance, which,
as it is known, is important for a description of the radiative neutron
capture. The phonon contribution to the pygmy-dipole resonance and to the
radiative neutron capture cross sections is increased with the (N-Z) difference
growth. For example, in the (0-10) MeV interval the full theory gives 17% of
EWSR for 150S n and 2.8% for 124S n, whereas within the continuum QRPA approach
we have 5.1% and 1.7%, respectively. These facts indicate an important role of
the self-consistent calculations that are of astrophysical interest for
neutron-rich nuclei. The comparison with the phenomenological Generalized
Lorentzian approach by Kopecky-Uhl has shown that the (Q)RPA approach gives a
significant increase in the cross section by a factor of 2 for 132S n and a
factor of 10 for 150S n and inclusion of the phonon coupling increases the
cross sections for these nuclei even more, by a factor of 2-3.
