Update of One-Loop Corrections for e~+e~- → f f-bar, First Run of SANC System

摘要

We present a description of calculations of the amplitude for the e~+e~- → f f-bar process with account of electroweak and QED one-loop corrections. This study is performed within the framework of the project SANC. The calculations are made within the OMS (on-mass-shell) renormalization scheme in two gauges: in R_ξ which allows an explicit control of gauge invariance by examining cancellation of gauge parameters and searching for gauge-invariant subsets of diagrams, and in the unitary gauge as a crosscheck. The formulas we derived are realized in two independent FORTRAN codes, eeffLib, which was written the old-fashioned way, i.e., manually, and another one, created automatically with the s2n. f (symbols to numbers) software-a part of the SANC system. We present a comprehensive comparison with the results of the well-known program ZFITTER for all the light fermion production channels, as well as will the results existing in the world literature for the process e~+e~- → t t-bar.