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On renormalons of static QCD potential at $u=1/2$ and $3/2$

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 نشر من قبل Hiromasa Takaura
 تاريخ النشر 2020
  مجال البحث
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We investigate the $u=1/2$ [$mathcal{O}(Lambda_{rm QCD})$] and $u=3/2$ [$mathcal{O}(Lambda_{rm QCD}^3)$] renormalons in the static QCD potential in position space and momentum space using the OPE of the potential-NRQCD effective field theory. This is an old problem and we provide a formal formulation to analyze it. In particular we present detailed examinations of the $u=3/2$ renormalons. We clarify how the $u=3/2$ renormalon is suppressed in the momentum-space potential in relation with the Wilson coefficient $V_A(r)$. We also point out that it is not straightforward to subtract the IR renormalon and IR divergences simultaneously in the multipole expansion. Numerical analyses are given, which clarify the current status of our knowledge on the perturbative series. The analysis gives a positive reasoning to the method for subtracting renormalons used in recent $alpha_s(M_Z)$ determination from the QCD potential.



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