  The spatial distributions of different ion species are useful indicators for
plasma sheet dynamics. In this statistical study based on 7 years of Cluster
observations, we establish the spatial distributions of oxygen ions and protons
at energies from 274 to 955 keV, depending on geomagnetic and solar wind (SW)
conditions. Compared with protons, the distribution of energetic oxygen has
stronger dawn-dusk asymmetry in response to changes in the geomagnetic
activity. When the interplanetary magnetic field (IMF) is directed southward,
the oxygen ions show significant acceleration in the tail plasma sheet. Changes
in the SW dynamic pressure ($\mathit{P}_{dyn}$) affect the oxygen and proton
intensities in the same way. The energetic protons show significant intensity
increases at the near-Earth duskside during disturbed geomagnetic conditions,
enhanced SW $\mathit{P}_{dyn}$, and southward IMF, implying there location of
effective inductive acceleration mechanisms and a strong duskward drift due to
the increase of the magnetic field gradient in the near-Earth tail. Higher
losses of energetic ions are observed in the dayside plasma sheet under
disturbed geomagnetic conditions and enhanced SW $\mathit{P}_{dyn}$. These
observations are in agreement with theoretical models.
