Precise Charm and Bottom Quark Masses
نویسندگان
چکیده
Exploiting the analyticity of the vacuum polarization function Π(q) around q = 0 and using dispersion relations, the derivatives at q = 0 can be expressed as weighted integrals over the imaginary part of Π(q), which in turn is given by the cross section for electronpositron annihilation into hadrons. Let us denote the normalised cross section for heavy quark production as RQ(s) ≡ σQ(s)/σpoint(s). The moments of RQ, defined as
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