We present a study of {\it finite} a and {\it volume} effects of the leptonic decay constant f of heavy pseudoscalar mesons in the static approximation. This study is performed on a number of lattices at β= 5.74,~6.0 and 6.26 covering sizes from about 0.7~fm to 2~fm. We confirm that beyond 1.5~fm the volume dependence is negligible. By carefully analysing results obtained using different trial wave functions for the heavy meson we find no dependence on the smearing. We also give results for the mass difference of the scalar - pseudoscalar and the Λb - pseudoscalar. Using the mass of the pseudoscalar meson we estimate the distance of string breaking in the static quark potential.
@article{arxiv.hep-lat/9211042,
title = {The Static Approximation of Heavy-Light Quark-Systems - A Systematic Lattice Study},
author = {C. Alexandrou and S. Guesken and F. Jegerlehner and K. Schilling and R. Sommer},
journal= {arXiv preprint arXiv:hep-lat/9211042},
year = {2009}
}