  We study a system of few fermions in a one-dimensional harmonic trap, and
focus on the case of dipolar majority particles in contact with a single
impurity. The impurity is used both for quenching the system, and for tracking
the system evolution after the quench. Employing exact diagonalization, we
investigate relaxation and thermalization properties. In the absence of dipolar
interactions, the system is near integrability, and the dynamics remains
oscillatory even on long time scales. On the other hand, repulsive as well as
attractive dipolar interactions lead to quick relaxation to the diagonal
ensemble average which is significantly different from corresponding thermal
averages. A Wigner-shaped level spacing distribution indicates level repulsion
and thus chaotic dynamical behavior due to the presence of dipolar
interactions.
