Quadrupole effects on the motion of extended bodies in Schwarzschild spacetime

The motion of an extended body up to the quadrupolar structure is studied in the Schwarzschild background following Dixon's model and within certain restrictions (constant frame components for the spin and the quadrupole tensor, center of mass moving along a circular orbit, etc). We find a number of interesting situations in which deviations from the geodesic motion, due to the internal structure of the particle, can originate measurable effects. However, the standard clock effect for a pair of co/counter-rotating bodies spinning up/down is not modified by the quadrupolar structure of the particle. © 2008 IOP Publishing Ltd.