论文标题
晶格QCD的电原理计算电动盒图的计算
First-principles calculation of electroweak box diagrams from lattice QCD
论文作者
论文摘要
我们介绍了与Beta衰减相关的$γW$盒图的第一个现实晶格QCD计算。 $γw$回路的非扰动低摩孔积分是使用晶状体QCD模拟计算得出的，并在高矩时与扰动QCD结果互补。以Pion半衰减的衰减为例，我们证明了该方法的可行性。通过使用带有多个晶格间距和体积的物理亲质量的域壁费，我们获得了轴向$γw$ -box校正到半蛋白蛋白pion decay的校正， $ \ box_ {γw}^{va} \ big |_π= 2.830（11）_ {\ Mathrm {stat}}}（26）_ {\ Mathrm {sys}}} \ times10^{ - 3} $，并在$ \ sim1 $ \ sim1 $ \ sim1 $ \ sims中控制不确定。这项研究阐明了$γw$ -box校正对中子衰变的第一原理计算，该腐烂在确定$ | v_ {ud} | $中起着决定性的作用。
We present the first realistic lattice QCD calculation of the $γW$-box diagrams relevant for beta decays. The nonperturbative low-momentum integral of the $γW$ loop is calculated using a lattice QCD simulation, complemented by the perturbative QCD result at high momenta. Using the pion semileptonic decay as an example, we demonstrate the feasibility of the method. By using domain wall fermions at the physical pion mass with multiple lattice spacings and volumes, we obtain the axial $γW$-box correction to the semileptonic pion decay, $\Box_{γW}^{VA}\big|_π=2.830(11)_{\mathrm{stat}}(26)_{\mathrm{sys}}\times10^{-3}$, with the total uncertainty controlled at the level of $\sim1$\%. This study sheds light on the first-principles computation of the $γW$-box correction to the neutron decay, which plays a decisive role in the determination of $|V_{ud}|$.
