| dc.description.abstract | We study applications of the Goldstone boson equivalence theorem to decay and scattering processes, exemplifying the broken gauge theory structure of electroweak interactions.
Apart from interest on theoretical grounds, we are motivated by the problem of
the dark matter identity, and the importance of electroweak bremsstrahlung
contributions to dark matter annihilation. Higgs decay into charged gauge bosons is
approached using four separate methods, including the utilisation of the
equivalence theorem, and we show that the results of all approaches agree.
Furthermore, the equivalence theorem is applied to electroweak bremsstrahlung
corrections in the specific process of quark production from electron-positron
annihilation. We find that the emission of the Goldstone boson intrinsically
has the appropriate high-energy behaviour, in contrast to the longitudinal
component of the massive gauge boson. Thus, the equivalence theorem necessitate
a cancellation of the longitudinal contributions from all sub-processes at a
given order in perturbation theory. | |
