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arXiv · hep-lat/0009038

Order a improved renormalization constants

Tanmoy Bhattacharya·Rajan Gupta·Weonjong Lee·Stephen Sharpe
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Abstract

We present non-perturbative results for the constants needed for on-shell $O(a)$ improvement of bilinear operators composed of Wilson fermions. We work at $β=6.0$ and 6.2 in the quenched approximation. The calculation is done by imposing axial and vector Ward identities on correlators similar to those used in standard hadron mass calculations. A crucial feature of the calculation is the use of non-degenerate quarks. We also obtain results for the constants needed for off-shell $O(a)$ improvement of bilinears, and for the scale and scheme independent renormalization constants, (Z_A), (Z_V) and (Z_S/Z_P). Several of the constants are determined using a variety of different Ward identities, and we compare their relative efficacies. In this way, we find a method for calculating $c_V$ that gives smaller errors than that used previously. Wherever possible, we compare our results with those of the ALPHA collaboration (who use the Schrödinger functional) and with 1-loop tadpole-improved perturbation theory.

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Tanmoy Bhattacharya, Rajan Gupta, Weonjong Lee, Stephen Sharpe. 2001-05-07. Order a improved renormalization constants. https://doi.org/10.1103/physrevd.63.074505

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