  We show that, in a many-body system, all particles can be strongly confined
to the initially occupied sites for a time that scales as a high power of the
ratio of the bandwidth of site energies to the hopping amplitude. Such
time-domain formulation is complementary to the formulation of the many-body
localization of all stationary states with a large localization length. The
long localization lifetime is achieved by constructing a periodic sequence of
site energies with a large period in a one-dimensional chain. The scaling of
the localization lifetime is independent of the number of particles for a broad
range of the coupling strength. The analytical results are confirmed by
numerical calculations.

Mesoscale and Nanoscale Physics;Disordered Systems and Neural Networks;Quantum Physics