Effect of emission of extra lepton pair for precise measurement of W-boson mass

Abstract

In the paper we present results for final state emissions of lepton pairs in decays of heavy intermediate states principally of Z boson, but of some importance for the W decays as well. The presented semi-analytical calculation and PHOTOS MC program are in numerical agreement to better than $5\%$ of pair effects. Suggestions for the future works are given.

Comments: 7 pages, 4 figures. Presented at "XXIII Cracow EPIPHANY Conference", 9 - 12 January 2017, Krakow, Poland. To be published in Acta Physica Polonica B