  We study dynamics of a Rouse polymer chain, which diffuses in a
three-dimensional space under the constraint that one of its ends, referred to
as the slip-link, may move only along a one-dimensional line containing
randomly placed, immobile, perfect traps. For such a model we compute exactly
the time evolution of the probability $P_{sl}(t)$ that the chain slip-link will
not encounter any of the traps until time $t$ and consequently, that until this
time the chain will remain mobile.
