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New Exact Heavy Quark Sum Rules

Nikolai Uraltsev
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Abstract

Considering nonforward scattering amplitude off the heavy quark in the Small Velocity limit two exact superconvergent sum rules are derived. The first sum rule leads to the lower bound ρ^2 > 3/4 for the slope of the Isgur-Wise function. It also provides the rationale for the fact that the vector heavy flavor mesons are heavier than the pseudoscalar ones. A spin-nonsinglet analogue \barΣof \barΛ= M_B-m_b is introduced.

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Nikolai Uraltsev. 2000-11-09. New Exact Heavy Quark Sum Rules. https://doi.org/10.1016/s0370-2693(01)00110-1

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