  Collisions of Au+Au have been studied at beam kinetic energies of 6, 8, and
10.8 GeV/nucleon at the AGS facility at Brookhaven National Laboratory.
Particles emitted from the collisions were momentum analyzed and identified in
a magnetic spectrometer system. Measurements were made at spectrometer angles
in the range 14deg - 59deg. m_t spectra of protons from central collisions were
analyzed to derive integrated rapidity distributions and inverse slope as a
function of rapidity. The results are compared with a thermal model and it is
concluded that there is either substantial transparency or longitudinal
expansion at all three beam energies.
