论文标题
$ b \至ππ\ ell \barν$过渡的晶格QCD研究
A lattice QCD study of the $B \to ππ\ell \barν$ transition
论文作者
论文摘要
$ v_ {ub} $是所有CKM矩阵元素中最小且最不知道的；当前社区主要通过独家过程$ b \toπ\ ell \barν$确定其幅度。在这里，我们介绍了从新颖过渡中的$ v_ {ub} $矩阵元素的晶格QCD确定的进度 - $ b \toππ\ ell \barν$过程，其中$ππ$ system in $ p $ wave in $ p $ wave and Scacting and Scationing具有$ρ（770）$ sonconance $ sonconance in s ins the Ens ancementa。我们对$ n_f = 2+1 $ s $ l \ l \ 3.6 $ fm和$ \ $ \ 320 $ meV的pion质量进行计算；对于$ b $ quark，我们使用各向异性三叶草动作。在简要介绍了理论框架之后，我们将讨论一些初步结果。
$V_{ub}$ is the smallest and least known of all CKM matrix elements; the community currently determines its magnitude primarily through the exclusive process $B\toπ\ell\barν$. Here we present our progress toward a lattice QCD determination of the $V_{ub}$ matrix element from a novel transition -- $B\toππ\ell\barν$ process, where the $ππ$ system is in a $P$ wave and scattering features the $ρ(770)$ resonance as an enhancement. We perform our calculation on $N_f=2+1$ isotropic clover fermions on a lattice of $L\approx 3.6$ fm and a pion mass of $\approx 320$ MeV; for the $b$-quark we use the anisotropic clover action. After a brief overview of the theoretical framework, we will discuss some preliminary results.
