Simultaneous optical polarimetry and X-ray data of the near-synchronous polar RX J2115-5840

We present simultaneous optical polarimetry and X-ray data of the near-sync hronous polar RX J2115-5840. We model the polarization data using the Stoke s imaging technique of fetter ct al. We find that the data are best modelle d using a relatively high binary inclination and a small angle between the magnetic and spin axes. We find that, for all spin-orbit beat phases, a sig nificant proportion of the accretion flow is directed on to the lower hemis phere of the white dwarf, producing negative circular polarization. Only fo r a small fraction of the beat cycle is a proportion of the flow directed o n to the upper hemisphere, However, the accretion flow never occurs near th e upper magnetic pole, whatever the orientation of the magnetic poles. This indicates the presence of a non-dipole field with the field strength at th e upper pole significantly higher. We find that the brightest parts of the hard X-ray emitting region and the cyclotron region are closely coincident.