Geometrical volume effects in the computation of the slope of the Isgur-Wise function
Abstract
We use a method recently suggested for evaluating the slope of the Isgur-Wise function, at the zero-recoil 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 finite-volume 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 Isgur-Wise 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:
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Nuclear Physics B
- Pub Date:
- February 1995
- DOI:
- 10.1016/0550-3213(95)00180-Z
- arXiv:
- arXiv:hep-lat/9410013
- Bibcode:
- 1995NuPhB.444..401L
- Keywords:
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- High Energy Physics - Lattice;
- High Energy Physics - Phenomenology
- E-Print:
- 25 pages, uuencoded compressed postscript file containing 11 figures, LaTeX, Edinburgh Preprint 94/548, Rome Preprint 94/1057 and Southampton Preprint SHEP 94/95-5