Neutrino Spin Flavor Precession and Leptogenesis

Abstract

We argue that ΔL=2 neutrino spin flavor precession, induced by the primordial magnetic fields, could have a significant impact on the leptogenesis process that accounts for the baryon asymmetry of the universe. Although the extra galactic magnetic fields is extremely weak at present time (about 10^{-9} Gauss), the primordial magnetic filed at the electroweak scale could be quite strong (of order 10^{17} Gauss). Therefore, at this scale, the effects of the spin flavor precession are not negligible. We show that the lepton asymmetry may be reduced by 50% due to the spin flavor precession. In addition, the leptogenesis will have different feature from the standard scenario of leptogenesis, where the lepton asymmetry continues to oscillate even after the electroweak phase transition.

5 pages, one figure. References added

References in corpus (5)

• Observation of Reactor Electron Antineutrino Disappearance in the RENO Experiment
• Search of Neutrino Magnetic Moments with a High-Purity Germanium Detector at the Kuo-Sheng Nuclear Power Station
• Cosmological lepton asymmetry with a nonzero mixing angle θ_{13}
• Constraint on the primordial vector mode and its magnetic field generation from seven-year Wilkinson Microwave Anisotropy Probe Observations
• Lepton asymmetries and the growth of cosmological seed magnetic fields