  The spin-split Fermi level crossings of the conduction band in Ni are mapped
out by high-resolution photoemission and compared to the equivalent crossing in
Cu. The area of the quasiparticle peak decreases rapidly below Ef in Ni, but
not in Cu. Majority spins have larger spectral weight at Ef than minority
spins, thereby enhancing the spin-polarization beyond that expected from the
density of states. A large part of the effect can be traced to a rapid
variation of the matrix element with {\bf k} at the point where the s,p-band
begins to hybridize with the $dz^2$ state. However, it is quite possible that
the intensity drop in Ni is reinforced by a transfer of spectral weight from
single-particle to many-electron excitations. The results suggest that the
matrix element should be considered for explaining the enhanced spin
polarization observed for Ni in spin-polarized tunneling.
