Resonant relativistic corrections and the Ay problem

We study relativistic corrections to nuclear interactions caused by boosting the two-nucleon interaction to a frame in which their total momentum does not vanish. These corrections induce a change in the computed value of the neutron-deuteron analyzing power A(y) that is estimated using the plane-wave impulse approximation. This allows a transparent analytical calculation that demonstrates the significance of relativistic corrections. Faddeev calculations are, however, needed to conclude on the A(y) puzzle.