A nonperturbative determination of the O(a) improvement coefficient c_A and the scaling of f_pi and m^{MSbar}
Loading...
Date
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Description
We report on an investigation of the LANL method for determining the O(a) improvement coefficient c_A nonperturbatively. We find we are able to extract reliable estimates for the coefficient using this method. However, our study of systematic errors shows that for very accurate determinations of c_A, the smearing function must be tuned and the volume fixed to keep the O(a) ambiguity in c_A fixed as beta varies. Consistency was found with previous results from the LANL group and (within fairly large errors) 1-loop perturbation theory; c_A does not change significantly over the range beta=5.93-6.2. The big difference between our results and those of the ALPHA collaboration, around beta=6.0, show that the O(a) differences in c_A between the different methods can be large. We find that the lattice spacing dependence of f_pi and the renormalised quark mass is much smaller using our values of the coefficient compared to those of the ALPHA collaboration.
19 pages revtex, 13 tables, 15 figures
19 pages revtex, 13 tables, 15 figures