The Effect of Baryonic Contribution to the U$_\textrm{Y}$(1) Chern-Simons Term on the Evolution of Fermionic Asymmetries and Hypermagnetic Fields
S. Rostam Zadeh, Siamak Sadat Gousheh · arXiv (Cornell University) · 2016
We study simultaneous evolution of baryon and the first generation lepton asymmetries and long range hypermagnetic fields in the temperature range $T_{EW} \sim 100$GeV$\leq T \leq 10$TeV, taking into account fermion number violation due to Abelian anomalies and the chirality flip reactions via inverse Higgs decays. More importantly, in addition to the usual contribution of the first generation leptonic chemical potentials, in this paper we also take into account the contribution of baryonic chemical potentials to the U$_\textrm{Y}$(1) Chern-Simons term which affects the evolution equations through AMHD equations. We solve the coupled equations for the fermion asymmetries and the hypermagnetic field to obtain their evolution as well as their final values at $T=T_{EW}$ for various critical ranges of initial values, and compare our results with those of our previous study. We find that, strong hypermagnetic fields make the asymmetries grow from their zero initial values. However, the final asymmetries are about 7 times smaller as compared to our previous study, while the final amplitude of the hypermagnetic field is a little larger. Moreover, almost $8$ times smaller matter asymmetries can amplify the hypermagnetic field with an initial amplitude of $10^{-2}$G to about $10$ times larger final amplitude of $10^{22}$G.