  In this article we present triple differential cross sections for equal
energy sharing kinematics for double photoionization of the helium atom at 20
and 40eV above threshold in the framework of the hyperspherical partial wave
theory. This supplements our earlier work \cite{DCP03} in which we were
successful in showing fully, gauge independence of the results in our
formalism. Also in this work we treat cases in which the Stokes parameter S$_1
< 1$ so that partial polarization of the photon source is also taken into
account. Agreement in shape with the Convergent Close Coupling \cite{BK03,HB98}
calculation and the experiments appears to be excellent.

Atomic Physics