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تسجيل مستخدم جديدSemileptonic Decay of $B$-Meson into $D^{**}$ and the Bjorken Sum Rule
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We study the semileptonic branching fraction of $B$-meson into higher resonance of charmed meson $D^{**}$ by using the Bjorken sum rule and the heavy quark effective theory(HQET). This sum rule and the current experiment of $B$-meson semileptonic decay into $D$ and $D^*$ predict that the branching ratio into $D^{**}l u_l$ is about 1.7%. This predicted value is larger than the value obtained by the various theoretical hadron models based on the HQET.
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