  The surface detector technique has been successfully used to detect cosmic
ray showers for several decades. Scintillators or Cerenkov water tanks can be
used to measure the number of particles and/or the energy density at a given
depth in the atmosphere and reconstruct the primary particle properties. It has
been shown that the experiment configuration and the resolution in
reconstructing the core position determine a distance to the shower axis in
which the lateral distribution function (LDF) of particles shows the least
variation with respect to different primary particles type, simulation models
and specific shapes of the LDF. Therefore, the signal at this distance (600 m
for Haverah Park and 1000 m for Auger Observatory) has shown to be a good
estimator of the shower energy. Revisiting the above technique, we show that a
range of distances to the shower axis, instead of one single point, can be used
as estimator of the shower energy. A comparison is done for the Auger
Observatory configuration and the new estimator proposed here is shown to be a
good and robust alternative to the standard single point procedure.
