  We report a detailed spectroscopic study of the electron doped cuprate
superconductor Pr(2-x)Ce(x)CuO(4-{\delta}) using point contact junctions for
x=0.125(underdoped), x=0.15(optimally doped) and x=0.17(overdoped). From our
conductance measurements we are able to identify bosonic resonances for each
doping. These excitations disappear above the critical temperature, and above
the critical magnetic field. We find that the energy of the bosonic excitations
decreases with doping, which excludes lattice vibrations as the paring glue. We
conclude that the bosonic mediator for these cuprates is more likely to be spin
excitations.
