The Isgur-Wise Function from the Lattice

Abstract

We calculate the Isgur-Wise function by measuring the elastic scattering amplitude of a $D$ meson in the quenched approximation on a $24^3\times 48$ lattice at $\beta =6.2$, using an $O(a)$-improved fermion action. We use this result, in conjunction with heavy-quark symmetry, to extract $|V_{cb}|$ from the experimentally measured $\bar{B}\to D^{\ast }l\bar{\nu }$\ differential decay width.

Comments: 3 pages, uuencoded compressed postscript file, to appear in the Proceedings of the International Europhysics Conference on High Energy Physics, Marseille, July 22-28, 1993. Southampton Preprint 93/94-06