Geometrical volume effects in the computation of the slope of the IsgurWise function
Abstract
We use a method recently suggested for evaluating the slope of the IsgurWise function, at the zerorecoil point, on the lattice. The computations are performed in the quenched approximation to lattice QCD, on a 24 ^{3} × 48 lattice at β = 6.2, using an 0( a)improved action for the fermions. We have found unexpectedly large finitevolume effects in such a calculation. These volume corrections turned out to be purely geometrical and independent of the dynamics of the system. After the study of these effects on a smaller volume and for different quark masses, we give approximate expressions that account for them. Using these approximations we find ξ'(1) = 1.7 _{2}^{+2} and ξ'(1) = 1.4 _{1}^{+2} for the slope of the IsgurWise function, for two mesons composed of a heavy quark slightly heavier and lighter, respectively, than the charm quark, and in both cases, a light antiquark whose mass is about that of the strange quark.
 Publication:

Nuclear Physics B
 Pub Date:
 February 1995
 DOI:
 10.1016/05503213(95)00180Z
 arXiv:
 arXiv:heplat/9410013
 Bibcode:
 1995NuPhB.444..401L
 Keywords:

 High Energy Physics  Lattice;
 High Energy Physics  Phenomenology
 EPrint:
 25 pages, uuencoded compressed postscript file containing 11 figures, LaTeX, Edinburgh Preprint 94/548, Rome Preprint 94/1057 and Southampton Preprint SHEP 94/955