Recently, a method for O(a) improvement of composite operators has been proposed which uses the large momentum behavior of fixed gauge quark and gluon correlation functions (G. Martinelli et al., hep-lat/0106003). A practical problem with this method is that a particular improvement coefficient, cNGI, which has a gauge non-covariant form, is difficult to determine. Here I work out the size of the errors made in improvement coefficients and physical quantities if one does not include the cNGI term.
Cite
@article{arxiv.hep-lat/0110021,
title = {Improved non-perturbative renormalization without $c_{NGI}$},
author = {Stephen R. Sharpe},
journal= {arXiv preprint arXiv:hep-lat/0110021},
year = {2009}
}