7,500 research outputs found
Axion Decay in a Constant Electromagnetic Background Field and at Finite Temperature using World-line Methods
We investigate the radiative decay of the axion into two photons in an
external electromagnetic field to one loop order. Our approach is based on the
world-line formalism, which is very suitable to take into account the external
field to all orders. Afterwards we discuss how the calculation could be
generalized to finite temperature.Comment: 27 pages, 4 figures, corrected and added some references and added
some remarks to appendix
Baryogenesis at the Electroweak Phase Transition for a SUSY Model with a Gauge Singlet
SUSY models with a gauge singlet easily allow for a strongly first order
electroweak phase transition (EWPT). We discuss the wall profile, in particular
transitional CP violation during the EWPT. We calculate CP violating source
terms for the charginos in the WKB approximation and solve the relevant
transport equations to obtain the generated baryon asymmetry.Comment: 5 pages, 6 figures. To appear in the Proceedings of Strong and
Electroweak Matter 2000 (SEWM2000), Marseilles; a reference adde
Coherent Baryogenesis and Nonthermal Leptogenesis: A comparison
We present a new mechanism for baryogenesis: at preheating after inflation
fermions acquire a varying mass by their coupling to a time dependent field.
Their CP-violating mass matrix can generate a charge asymmetry to be
transformed into a lepton asymmetry through decay into standard model particles
and heavy Majorana neutrinos. In a concrete model of hybrid inflation we
compare ``coherent baryogenesis'' with nonthermal leptogenesis by perturbative
decay of the inflation condensates.Comment: 6 pages, 2 figures, contribution to the Proceedings of Strong and
Electroweak Matter 2004 (SEWM2004), Helsinki, Finland, June 16-19, 200
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