  We consider one of the variants of obtaining the longitudinal polarization of
electrons in the SuperB HER at 7 GeV. The spin rotators include the solenoids.
The time of polarization relaxation due to the SR processes in the bend magnets
of the main arcs is calculated depending on the beam energy and taking into
account betatron oscillations. A comparison of the radiation polarization
relaxation time with the beam lifetime due to the high luminosity makes it
possible to evaluate the efficiency of the longitudinal polarization scheme.
