Green Jeremy, Gryniuk Oleksii, von Hippel Georg, Meyer Harvey B, Pascalutsa Vladimir
PRISMA Cluster of Excellence and Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany.
Taras Shevchenko Kyiv National University, Volodymyrska 60, UA-01033 Kyiv, Ukraine.
Phys Rev Lett. 2015 Nov 27;115(22):222003. doi: 10.1103/PhysRevLett.115.222003. Epub 2015 Nov 25.
We perform a lattice QCD calculation of the hadronic light-by-light scattering amplitude in a broad kinematical range. At forward kinematics, the results are compared to a phenomenological analysis based on dispersive sum rules for light-by-light scattering. The size of the pion pole contribution is investigated for momenta of typical hadronic size. The presented numerical methods can be used to compute the hadronic light-by-light contribution to the anomalous magnetic moment of the muon. Our calculations are carried out in two-flavor QCD with the pion mass in the range of 270-450 MeV and contain so far only the diagrams with fully connected quark lines.
我们在宽广的运动学范围内对强子的光致光散射振幅进行格点量子色动力学计算。在前向运动学情况下，将结果与基于光致光散射色散求和规则的唯象分析进行比较。针对典型强子大小的动量，研究了π介子极点贡献的大小。所提出的数值方法可用于计算强子对μ子反常磁矩的光致光贡献。我们的计算是在双味量子色动力学中进行的，π介子质量范围为270 - 450 MeV，目前仅包含具有完全连接夸克线的图。
