Next-to-leading order corrections are an important aspect in the extractionof the Cabibbo- Kobayashi-Maskawa matrix elements $|V_{\text{cb}}|$ and$|V_{\text{ub}}|$ at $B$-factory experiments: virtual and real photons coupleto all charged particles of the decay, alter the resulting decay dynamics andenhance the total decay rate. We present a phenomenologically motivated modeland a Monte-Carlo implementation to study electromagnetic radiative correctionsto differential and total decay rates for semileptonic $B$-meson decays intoexclusive pseudoscalar and scalar final states and apply it to $B \to D \, l \,\nu$ and $B \to \pi \, l \, \nu$, and $B \to D_0^* \, l \, \nu$ decays,respectively. We study such corrections with a phenomenological picture ofpoint-like mesons (with some structure-dependent corrections), which is validin the low-energy region of the photons and whose results we extrapolate overthe complete phase space. The largest quantifiable uncertainty is due to theapproximative matching to the Standard Model. In addition unknownstructure-dependent contributions and model dependencies might have an impacton our findings.
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机译：在提取$$ B的Cabibbo- Kobayashi-Maskawa矩阵元素$ | V _ {\ text {cb}} | $和$ | V _ {\ text {ub}} | $时，从前至后的顺序校正是一个重要方面。工厂实验：虚拟光子和真实光子耦合到衰变的所有带电粒子，改变最终的衰变动力学并提高总衰变率。我们提出了一个现象学动机模型和一个蒙特卡洛实现方法，以研究电磁辐射校正，以将半瘦子$ B $-介子衰变成排他的伪标量和标量最终状态的微分和总衰减率应用到$ B \ to D \，l \，\ nu $和$ B \到\ pi \，l \，\ nu $和$ B \到D_0 ^ * \，l \，\ nu $分别衰减。我们使用点状介子的现象学图片（具有一些与结构有关的校正）来研究此类校正，该校正在光子的低能区域有效，并且我们可以将其结果外推到整个相空间。可量化的最大不确定性是由于与标准模型的近似匹配。此外，未知的结构依赖性贡献和模型依赖性可能会对我们的发现产生影响。
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