Perturbative calculation of O(a) improvement coefficients
Abstract
We compute several coefficients needed for O(a) improvement of currents in perturbation theory, using the BrodskyLepageMackenzie prescription for choosing an optimal scale q^{*}. We then compare the results to nonperturbative calculations. Normalization factors of the vector and axial vector currents show good agreement, especially when allowing for small twoloop effects. On the other hand, there are large discrepancies in the coefficients of O(a) improvement terms. We suspect that they arise primarily from power corrections inherent in the nonperturbative methods.
 Publication:

Physical Review D
 Pub Date:
 January 2003
 DOI:
 10.1103/PhysRevD.67.014503
 arXiv:
 arXiv:heplat/0208004
 Bibcode:
 2003PhRvD..67a4503H
 Keywords:

 11.15.Ha;
 12.38.Cy;
 Lattice gauge theory;
 Summation of perturbation theory;
 High Energy Physics  Lattice
 EPrint:
 14pp, 3 figs (8 plots)