论文标题
局部有限的双环振幅，用于电子脉络体歼灭中的壳多光子生产
Locally finite two-loop amplitudes for off-shell multi-photon production in electron-positron annihilation
论文作者
论文摘要
我们研究了两循环QED振幅的奇异性结构，用于在无质量的电子脉络体歼灭中产生多个脱壳光子，并发展反对者，以消除环路内地中点的紫外线和紫外线脱落。减法的剩余部分是四个维度的整合，可以在将来通过数值集成来计算。反行词捕获了振幅的差异，并根据出生幅度和一环振幅的有限剩余而分解。它们由简单的单循环积分和最多三个外部动量组成，并且可以通过既定方法以简单的方式进行分析。我们揭示了完全局部IR分解的新方面，其中必须通过对环动量的新对称性来修改顶点和自我能源细分，以便在循环整合之前揭示其类似树状的张量结构，从而使IR奇异性的分解。这项工作是迈向局部隔离一般规程理论振幅的艰苦贡献的第一步，并通过数值方法将它们恰好在四个维度中进行整合。
We study the singularity structure of two-loop QED amplitudes for the production of multiple off-shell photons in massless electron-positron annihilation and develop counterterms that remove their infrared and ultraviolet divergences point by point in the loop integrand. The remainders of the subtraction are integrable in four dimensions and can be computed in the future with numerical integration. The counterterms capture the divergences of the amplitudes and factorize in terms of the Born amplitude and the finite remainder of the one-loop amplitude. They consist of simple one- and two-loop integrals with at most three external momenta and can be integrated analytically in a simple manner with established methods. We uncover novel aspects of fully local IR factorization, where vertex and self-energy subdiagrams must be modified by new symmetrizations over loop momenta, in order to expose their tree-like tensor structures and hence factorization of IR singularities prior to loop integration. This work is a first step towards isolating locally the hard contributions of generic gauge theory amplitudes and rendering them integrable in exactly four dimensions with numerical methods.
