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arXiv · 1608.00068

Scheme-Independent Calculation of $\gamma_{\bar\psi\psi,IR}$ for an SU(3) Gauge Theory

Thomas A. Ryttov·Robert Shrock
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Abstract

We present a scheme-independent calculation of the infrared value of the anomalous dimension of the fermion bilinear, $\gamma_{\bar\psi\psi,IR}$ in an SU(3) gauge theory as a function of the number of fermions, $N_f$, via a series expansion in powers of $\Delta_f$, where $\Delta_f=(16.5-N_f)$, to order $\Delta_f^4$. We perform an extrapolation to obtain the first determination of the exact $\gamma_{\bar\psi\psi,IR}$ from continuum field theory. The results are compared with calculations of the $n$-loop values of this anomalous dimension from series in powers of the coupling and from lattice measurements.

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Thomas A. Ryttov, Robert Shrock. 2016-07-30. Scheme-Independent Calculation of $\gamma_{\bar\psi\psi,IR}$ for an SU(3) Gauge Theory. https://doi.org/10.1103/physrevd.94.105014

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