  The STAR Collaboration at RHIC presents a systematic study of high transverse
momentum charged di-hadron correlations at small azimuthal pair separation
\dphino, in d+Au and central Au+Au collisions at $\rts = 200$ GeV. Significant
correlated yield for pairs with large longitudinal separation \deta is observed
in central Au+Au, in contrast to d+Au collisions. The associated yield
distribution in \detano$\times$\dphi can be decomposed into a narrow jet-like
peak at small angular separation which has a similar shape to that found in
d+Au collisions, and a component which is narrow in \dphi and
\textcolor{black}{depends only weakly on} $\deta$, the "ridge". Using two
systematically independent analyses, \textcolor{black}{finite ridge yield} is
found to persist for trigger $\pt > 6$ \GeVc, indicating that it is correlated
with jet production. The transverse momentum spectrum of hadrons comprising the
ridge is found to be similar to that of bulk particle production in the
measured range ($2 < \pt < 4 \GeVc$).
