  Coalescence of minijet partons with the partons from the quark-gluon plasma
formed in relativistic heavy ion collisions is suggested as the mechanism for
production of hadrons with intermediate transverse momentum. The resulting
enhanced antiproton and pion yields at intermediate transverse momentum gives a
plausible explanation for the observed large antiproton to pion ratio. With
further increasing momentum, the ratio is predicted to decrease and approach
the small value given by independent fragmentations of minijet partons after
their energy loss in the quark-gluon plasma.
