论文标题
$ d _ {(s)} $ mesons的半衰减衰减
Semileptonic decays of $D_{(s)}$ mesons
论文作者
论文摘要
对量子场理论中的介子结合状态的对称性的连续方法,用于描述许多$π$ - 和$ k $ -Meson electroweak过程,用于分析Leptonic和semileptonic衰减的$ D _ {(s)} $ Mesons $ Mesons。通常,每个半雌性过渡的特征在于$ t = 0 $的主要形式的值,此处获得以下结果:$ f _+^{d_s \ to k}(0)= 0.673(40)$; $ f _+^{d \toπ}(0)= 0.618(31)$;和$ f _+^{d \ to k}(0)= 0.756(36)$。处理这些形式的计算$ t $依赖性和$ | v_ {cd} | $,$ | v_ {cs} | $的标准平均值,一个人对相关的分支分数进行以下预测:$ {\ cal b} _ {d_s^+ \ to k^+ \ to k^0 e^0 e^+ n e^3.31 10^{ - 3} $; $ {\ cal b} _ {d^0 \toπ^ - e^+ν_e} = 2.73(22)\ times 10^{ - 3} $;和$ {\ cal b} _ {d^0 \ to k^ - e^+ν_e} = 3.83(28)$%。另外,使用计算出的$ t $依赖性,与这些分支分数的现代经验结果达成协议,需要$ | v_ {cd} | = 0.221(9)$,$ | v_ {us} | = 0.953(34)$。有了所有$ d _ {(s)} $过渡形式,可以分析SU $(3)$ - 风味对称性的性质,可以分析一系列过程中的风味对称性;就像在$π$ - $ k $行业中一样,这种效果的大小是由标准模型中与新兴质量产生相关的量表确定的,而不是源自HIGGS机制的量表。
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.