  The usual nuclear recoil energy reconstruction employed by liquid xenon dark
matter search experiments relies only on the primary scintillation photon
signal. Energy reconstruction based on both the photon and electron signals
yields a more accurate representation of search results. For a dark matter
particle mass m~10 GeV, a nuclear recoil from a scattering event is more likely
to be observed in the lower left corner of the typical search box, rather than
near the nuclear recoil calibration centroid. In this region of the search box,
the actual nuclear recoil energies are smaller than the usual energy scale
suggests, by about a factor x2. Recent search results from the XENON100
experiment are discussed in light of these considerations.
