  New break-junction tunneling data are reported in Bi2Sr2CaCu2O(8+delta) over
a wide range of hole concentration from underdoped (Tc = 74 K) to optimal doped
(Tc = 95 K) to overdoped (Tc = 48 K). The conductances exhibit sharp dips at a
voltage, Omega/e, measured with respect to the superconducting gap. Clear
trends are found such that the dip strength is maximum at optimal doping and
that Omega scales as 4.9 kTc over the entire doping range. These features link
the dip to the resonance spin excitation and suggest quasiparticle interactions
with this mode are important for superconductivity.
