$B\to \ddot{I}€l\bar{\hat{I}}½$ Form Factors with NRQCD Heavy Quark and Clover Light Quark Actions

Abstract

We report results on semileptonic $B\to \ddot{I}€l\bar{\hat{I}}½$ decay form factors near $q_{\max }^2$ using NRQCD heavy quark and clover light quark actions and currents improved through $O(\hat{I}\pm a)$. An inconsistency with the soft pion relation $f^0(q_{\max }^2)=f_B/f_{\ddot{I}}€$ found in a previous work is confirmed, and a possible solution with nonperturbative renormalization is discussed. We find that $f^{+}(q^2)$ is well described by the $B^{\ast }$ pole near $q_{\max }^2$, and its $1/M_B$ scaling is also consistent with the prediction of the pole dominance model.

LATTICE99, 3 pages, 3 figures