Sum - rule for large - N c QCD and application to heavy quarkonia 1
نویسندگان
چکیده
We introduce a new sum-rule for large-N c QCD which relates the density of heavy quarkonium states, the state-averaged square of the wave-function at the origin, and the heavy quark current-current correlator. Focusing on the region of energy just above perturbative threshold, we calculate the correlator by incorporating arbitrarily high orders in the QCD coupling α s. We use the sum-rule to determine the bottomo-nium potential using experimentally measured s-wave leptonic widths and compare the result with the potential obtained by direct calculation from the measured s-wave spectrum. We discuss the utility of the sum-rule method for accurate determination of the confining potential.
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