arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新，休息一下吧，周末愉快~~
arXiv 2003.04420hep-phhep-exhep-latnucl-exnucl-th
收藏

$D_{(s)}$介子的半轻子衰变

Semileptonic decays of $D_{(s)}$ mesons

Zhao-Qian Yao, Daniele Binosi, Zhu-Fang Cui, Craig D. Roberts, Shu-Sheng Xu, Hong-Shi Zong

备注：
9 pages, 5 figures, 4 tables
发表信息：
Phys. Rev. D 102, 014007 (2020)
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

在量子场论中，介子束缚态的保序连续方法曾在其他地方用来描述许多$π$ -和$K$ -介子电弱过程，本文用来分析$D_{(s)}$介子的轻子和半轻子衰变。每个半轻子跃迁通常由在$t=0$处的主导形状因子的值来表征，并且在此获得以下结果：$f_+^{D_s\to K}(0) = 0.673(40)$ ; $f_+^{D\to π}(0)=0.618(31)$ ;和$f_+^{D\to K}(0)=0.756(36)$。使用这些形状因子的计算的$t$依赖性和$|V_{cd}|$、$|V_{cs}|$的标准平均值，得到相关分支分数的以下预测：${\cal B}_{D_s^+\to K^0 e^+ ν_e} = 3.31(33)\times 10^{-3}$ ; ${\cal B}_{D^0\to π^- e^+ ν_e} = 2.73(22)\times 10^{-3}$ ;和${\cal B}_{D^0\to K^- e^+ ν_e} = 3.83(28)$ %。或者，使用计算的$t$依赖性，与当代经验结果的这些分支分数的协议需要$|V_{cd}|=0.221(9)$，$|V_{us}|=0.953(34)$。掌握了所有的$D_{(s)}$跃迁形状因子，就可以分析这一系列过程中SU $(3)$的性质--味破缺;就像在$π$-$K$扇区中一样，发现这种效应的大小是由标准模型中与突现质量产生相关的尺度决定的，而不是由希格斯机制产生的尺度决定的。

英文摘要：

A symmetry-preserving continuum approach to meson bound-states in quantum field theory, employed elsewhere to describe numerous $π$- and $K$-meson electroweak processes, is used to analyse leptonic and semileptonic decays of $D_{(s)}$ mesons. Each semileptonic transition is conventionally characterised by the value of the dominant form factor at $t=0$ and the following results are obtained herein: $f_+^{D_s\to K}(0) = 0.673(40)$; $f_+^{D\to π}(0)=0.618(31)$; and $f_+^{D\to K}(0)=0.756(36)$. Working with the computed $t$-dependence of these form factors and standard averaged values for $|V_{cd}|$, $|V_{cs}|$, one arrives at the following predictions for the associated branching fractions: ${\cal B}_{D_s^+\to K^0 e^+ ν_e} = 3.31(33)\times 10^{-3}$; ${\cal B}_{D^0\to π^- e^+ ν_e} = 2.73(22)\times 10^{-3}$; and ${\cal B}_{D^0\to K^- e^+ ν_e} = 3.83(28)$%. Alternatively, using the calculated $t$-dependence, agreement with contemporary empirical results for these branching fractions requires $|V_{cd}|=0.221(9)$, $|V_{us}|=0.953(34)$. With all $D_{(s)}$ transition form factors in hand, the nature of SU$(3)$-flavour symmetry-breaking in this array of processes can be analysed; and just as in the $π$-$K$ sector, the magnitude of such effects is found to be determined by the scales associated with emergent mass generation in the Standard Model, not those originating with the Higgs mechanism.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑