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 ($2 < pt < 4 GeVc$).
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