Final State Radiative Effects for the Exact O(alpha) YFS Exponentiated (Un)Stable W+W- Production At and Beyond LEP2 Energies

Abstract

We present the LL final state radiative effects for the exact O(alpha) YFS exponentiated (un)stable WW pair production at LEP2/NLC energies using Monte Carlo event generator methods. The respective event generator, version 1.12 of the program YFSWW3, wherein both Standard Model and anomalous triple gauge boson couplings are allowed, generates n(γ) radiation both from the initial state and from the intermediate W+ W- and generates the LL final state W decay radiative effects. Sample Monte Carlo data are illustrated.

Figures (8)

• Figure 1: The invariant mass distributions of $W^-$ reconstructed from its decay products, $e^- \bar{\nu_e}$, four-momenta. In the left pictures the electron is treated exclusively ('bare' electron), while in the right pictures it is treated calorimetrically ('dressed' electron -- its four-momentum is combined with four-momenta of all photons emitted within an angle of $5^\circ$ around its direction). The input values are $M_W = 80.23$ GeV, $\Gamma_W= 2.034$ GeV.
• Figure 2: The angular distributions of $W^-$ reconstructed from its decay products, $e^- \bar{\nu_e}$, four-momenta. In the left pictures the electron is treated exclusively ('bare' electron), while in the right pictures it is treated calorimetrically as defined in Fig. 1.
• Figure 3: The distributions of the final state electron energy in the LAB frame. In the left pictures the electron is treated exclusively ('bare' electron), while in the right pictures it is treated calorimetrically as defined in Fig. 1.
• Figure 4: The distributions of the electron decay angle's cosine in the $W^-$ rest frame. In the left pictures the electron is treated exclusively ('bare' electron), while in the right pictures it is treated calorimetrically as defined in Fig. 1.
• Figure 5: The invariant mass distributions of $W^-$ reconstructed from its decay products, $\mu^- \bar{\nu_{\mu}}$, four-momenta. In the left pictures the muon is treated exclusively ('bare' muon), while in the right pictures it is treated calorimetrically as defined in Fig. 1. The input values are $M_W = 80.23$ GeV, $\Gamma_W = 2.034$ GeV.