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arXiv · hep-lat/9911036

$B \to πl\barν$ Form Factors with NRQCD Heavy Quark and Clover Light Quark Actions

JLQCD Collaboration·S. Aoki·M. Fukugita·S. Hashimoto·K-I. Ishikawa·N. Ishizuka·Y. Iwasaki·K. Kanaya·T. Kaneda·S. Kaya·Y. Kuramashi·M. Okawa·T. Onogi·S. Tominaga·N. Tsutsui·A. Ukawa·N. Yamada·T. Yoshié
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Abstract

We report results on semileptonic $B\toπl\barν$ decay form factors near $q^2_{\rm max}$ using NRQCD heavy quark and clover light quark actions and currents improved through $O(αa)$. An inconsistency with the soft pion relation $f^0(q^2_{\rm max})= f_B/f_π$ 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 $B^*$ pole near $q^2_{\rm max}$, and its $1/M_B$ scaling is also consistent with the prediction of the pole dominance model.

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JLQCD Collaboration, S. Aoki, M. Fukugita, S. Hashimoto, K-I. Ishikawa, N. Ishizuka, Y. Iwasaki, K. Kanaya, T. Kaneda, S. Kaya, Y. Kuramashi, M. Okawa, T. Onogi, S. Tominaga, N. Tsutsui, A. Ukawa, N. Yamada, T. Yoshié. 1999-11-29. $B \to πl\barν$ Form Factors with NRQCD Heavy Quark and Clover Light Quark Actions. https://doi.org/10.1016/s0920-5632(00)91662-1

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