  A model of quasistationary states is constructed for the one-dimensional edge
states propagating along the edge of a two-dimensional topological insulator
based on HgTe/CdTe quantum well in the presence of magnetic barriers with
finite transparency. The lifetimes of these quasistationary states are found
analytically and numerically via different approaches including the solution of
the stationary Schroedinger equation with complex energy and the solution of
the transmission problem for a double barrier structure. The results can serve
as a guide for determining the parameters of magnetic barriers creating the
quantum dots where the lifetimes for the broadened discrete levels are long
enough for manipulation with their occupation numbers by external fields.
