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arXiv · 1807.11616

NSPT estimate of the improvement coefficient $c_A$ to two loops

Christian Torrero
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Abstract

By using Numerical Stochastic Perturbation Theory (NSPT), we carry out a quenched two-loop computation of the improvement coefficient $c_A$ associated to the isovector axial current. Within the Schrödinger Functional formalism, we compute the bare quark mass $m$ and fix $c_A$ by requiring discretization corrections on $m$ to be of order $O(a^2)$ in the lattice spacing $a$.

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Christian Torrero. 2019-02-08. NSPT estimate of the improvement coefficient $c_A$ to two loops. https://doi.org/10.1103/physrevd.99.014517

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