Measurement of $|V_{ub}|$ in semi-inclusive charmless $B\to \pi X$ decays

Abstract

We study semi-inclusive charmless decays $B\to \pi X$, where $X$ does not contain a charm (anti)quark. The mode ${\bar{B}}^0\to {\pi }^{-}X$ turns out to be be particularly useful for determination of the CKM matrix element $|V_{ub}|$. We present the branching ratio (BR) of ${\bar{B}}^0\to {\pi }^{-}X$ as a function of $|V_{ub}|$, with an estimation of possible uncertainty. The BR is expected to be an order of $10^{-4}$.

Comments: 3 pages, 2 figures, Proceedings of the Fifth KEK Topical Conference