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Study of 1/m corrections in HQET

Shunsuke Negishi·Hideo Matsufuru·Tetsuya Onogi·Takashi Umeda
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Abstract

We report our exploratory study on the matching condition of HQET with QCD including 1/m corrections. We introduce a new observable from the dependence of the heavy-light effective energy on the twisted boundary condition parameter $θ$, which could be used to match the kinetic term $\vec{D}^2/(2m)$. Carrying out quenched QCD simulations for fixed lattice spacing in small volumes with O(a)-improved Wilson fermions, we study the 1/m dependence of this observable, from which the static limit and 1/m coefficient can be extracted. We also compare our preliminary result with HQET.

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Shunsuke Negishi, Hideo Matsufuru, Tetsuya Onogi, Takashi Umeda. 2005-10-07. Study of 1/m corrections in HQET. https://arxiv.org/abs/hep-lat/0510048

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