Cosmological abundances of right-handed Dirac neutrinos
Abstract
Description
The equilibration of the right-helicity states $ν_+$ of light Dirac-neutrinos is discussed. I point out that the $ν_+$ production rate is enhanced by weak gauge boson pole effects so that the right-helicity component of $ν_τ$ is brought into equilibrium at $T\simeq 10$ GeV independently of the initial abundance, provided $m_{ν_τ}\gsim 10$ keV. Neutrino spin flip in primordial magnetic fields and the resulting bound on $μ_ν$ is also discussed.
Talk given at the Neutrino '96 Conference. 5 pages, LaTeX, 3 ps figures included
Talk given at the Neutrino '96 Conference. 5 pages, LaTeX, 3 ps figures included