Kinetic description of W and Z boson creation in the early universe
D. B. Blaschke, M. P. Dabrowski, V. V. Dmitriev, S. A. Smolyansky
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4 pages, contribution to the Proceedings of the XIX Int. Baldin Seminar on High Energy Physics Problems "Relativistic Nuclear Physics and QCD", Dubna, 29.9.-4.10.2008
We consider an alternative mechanism for the production of the cosmic microwave background (CMB) radiation. It is basically due to vacuum pair creation (VPC) of vector bosons (W and Z) as a consequence of a rapid W and Z mass generation during the electroweak phase transition in the early Universe. The mechanism is as follows: after their pair crreation, the vector bosons may either annihilate directly into photons or decay into leptons and quarks which subsequently annihilate as lepton-antilepton and quark-antiquark pairs into photons. Preliminary estimates show that the number of CMB photons obtained this way can be sufficient to explain the presently observed CMB photon density. In this contribution we present an exactly soluble model for vacuum pair creation kinetics.
Extensions of the Standard Model of particle physics with new Abelian gauge groups allow for kinetic mixing between the new gauge bosons and the hypercharge gauge boson, resulting in mixing with the photon. In many models the mixing with the hypercharge gauge boson captures only part of the kinetic mixing term with the photon, since the new gauge bosons can also mix with the neutral component of the $SU(2)_L$ gauge bosons. We take these contributions into account and present a consistent description of kinetic mixing for general Abelian gauge groups both in the electroweak symmetric and the br…
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