使用Oktay-Kronfeld作用量计算半轻$B \to D^{(\ast)} \ellν$衰变形状因子

使用Oktay-Kronfeld action计算零反冲时的$\bar B \rightarrow D^\ast \ell \bar ν$形状因子

Calculation of $\bar B \rightarrow D^\ast \ell \bar ν$ form factor at zero recoil using the Oktay-Kronfeld action

利用格点量子色动力学计算了四种海夸克的$\bar B \rightarrow D^\ast \ell \bar ν$衰变的零反冲下半轻子形状因子$h_{A_1}(w=1)/ρ_{A_j}$的第一个初步结果。我们对轻价夸克和海夸克采用HISQ交错作用量（MILC HISQ组态），对重价夸克采用Oktay-Kronfeld（OK）作用量。

用Oktay-Kronfeld重夸克计算$\bar{B}\to D^{(*)}\ell\barν$形状因子的重-重流改进

Improvement of heavy-heavy current for calculation of $\bar{B}\to D^{(*)}\ell\barν$ form factors using Oktay-Kronfeld heavy quarks

CKM矩阵元$|V_{cb}|$可以通过将实验数据与$\bar{B}\to D^{(*)} \ell \barν$衰变的半轻子形状因子的格点量子色动力学结果相结合来提取。Oktay-Kronfeld（OK）作用量的设计是为了将重夸克离散化误差降低到$1\%$以下，或者通过HQET功率计数中的$\mathcal{O}(λ^3)$。在这里，我们描述了最近的进展，底部的魅力电流改善到相同的顺序在HQET的OK行动，并纠正以前报道的结果，我们的匹配计算，其中运营商的基础是不完整的。

Oktay-Kronfeld Action的重介子谱实验

Heavy-Meson Spectrum Tests of the Oktay--Kronfeld Action

本文给出了用Oktay-Kronfeld作用量在MILC asqtad晶格上得到的重介子谱结果。OK作用量是为了改进费米实验室公式中的重夸克作用量，从而减小重夸克离散化误差而设计的。OK作用量包含了6维和7维算子，这些算子是通过对重轻介子的序$\mathrm{O}(Λ^3/m_Q^3)$和对夸克偶素的序$\mathrm{O}(v^6)$，或者等价地通过$\mathrm{O}(a^2)$和一些具有Symanzik幂计数的$\mathrm{O}(a^3)$项与QCD进行树级匹配所必需的。为了评估改进，我们扩展了以前的数值试验与重介子质量通过分析数据上产生的更精细（$a \approx 0.12\;$调频）晶格与正确的蝌蚪因子的$c_5$长期的行动。我们更新的不一致性参数和超精细分裂的休息和动力质量的分析。

Current progress on the semileptonic form factors for $\bar{B} \to D^{\ast} \ell \barν$ decay using the Oktay-Kronfeld action

We present recent progress in calculating the semileptonic form factors $h_{A_1}(w)$ for the $\bar{B} \to D^{\ast} \ell \barν$ decays. We use the Oktay-Kronfeld (OK) action for the charm and bottom valence quarks and the HISQ action for light quarks. We adopt the Newton method combined with the scanning method to find a good initial guess for the $χ^2$ minimizer in the fitting of the 2pt correlation functions. The main advantage is that the Newton method lets us to consume all the time slices allowed by the physical positivity. We report the first, reliable, but preliminary results for $h_{A_1…

Improvement of heavy-heavy and heavy-light currents with the Oktay-Kronfeld action

The CKM matrix elements $V_{cb}$ and $V_{ub}$ can be obtained by combining data from the experiments with lattice QCD results for the semi-leptonic form factors for the $\bar{B} \to D^\ast \ell \barν$ and $\bar{B} \to π\ell \barν$ decays. It is highly desirable to use the Oktay-Kronfeld (OK) action for the form factor calculation on the lattice, since the OK action is designed to reduce the heavy quark discretization error down to the $\mathcal{O}(λ^4)$ level in the power counting rules of the heavy quark effective theory (HQET). Here, we present a matching calculation to improve heavy-heavy a…

用Oktay-Kronfeld action计算$\bar{B}\rightarrow D^{(*)}\ell \barν$半轻子形状因子的重-重流改进

Heavy-heavy current improvement for calculation of $\bar{B}\rightarrow D^{(*)}\ell \barν$ semi-leptonic form factors using the Oktay-Kronfeld action

$\bar{B}\to D^{(*)}\ell\barν$衰变的形状因子的晶格计算可用于提取CKM矩阵元素$|V_{cb}|$。Oktay-Kronfeld作用量是费米实验室作用量的一个高度改进的版本，它通过HQET功率计数中的$\mathcal{O}(λ^3)$系统地减少了重夸克离散化效应，用于重-轻介子量。为了用Oktay-Kronfeld重夸克计算$\bar{B}\rightarrow D^{(*)}\ell \barν$半轻子形状因子，我们需要将重夸克流改进到相同的水平。本文报道了我们在计算底夸克和粲夸克组成的流的改进系数方面的进展。本文的结果是初步的。