Distribution functions for heavy vector bosons inside colliding particle beams

Strongly interactingWWsystem: Gold-plated modes

“…We first compute the cross sections for WL W, production in a given model by using the effective W approximation (EWA) [4,5] and the equivalence theorem (ET) [I-31. In using the EWA, we compute total cross sections, subject leptonic cuts, ignoring all jet observables. To assess the inaccuracies that might arise as a result of these approximations, we will make a detailed comparison between the EWA and ET computations and the exact SM calculation in Sec.…”

“…This is both a computational and conceptual simplification, for it allows us to draw on our considerable experience with Goldstone-boson scattering in QCD. We will also use the effective W approximation [4,5] to connect the WL WL subprocesses to the pp initial state.…”

QCD corrections to single top quark production in electron-photon interactions

“…This is the essence of the so called effective W -boson approximation [64,65,66,58,67]. In this approach the intermediate W -bosons is considered on-shell and described through structure functions similar to the afore mentioned structure function approach for the b-quark.…”

“…The effective W -approximation is similar to the Weizsäcker-Williams [68] approximation. The total cross section for ℓ + γ → tbν ℓ in this approach is then given by [64,65,66,58,67] σ(ℓ Note that we have written down only the leading terms for the structure functions. The 'subleading' terms which are suppressed by additional powers of m w 2 /s are not universal and depend on the exact prescription how to define them.…”

Probing strongly interacting W’s at the ILC with polarized beams

“…[18][19][20][21]. Gauge boson scatterings in processes like qq → qqV V , where V = W, Z were computed within, what is known as, the equivalent gauge boson approximation (EGBA) [22][23][24][25][26]. In such an approximation the V V scattering cross section is folded with the probability distribution of W and Z bosons contained in the proton.…”