Physics – High Energy Physics – High Energy Physics - Phenomenology
Scientific paper
2000-08-24
Astropart.Phys.17:245-261,2002
Physics
High Energy Physics
High Energy Physics - Phenomenology
33 pp, 7 figures
Scientific paper
10.1016/S0927-6505(01)00155-4
Oscillations of active to sterile neutrinos with a small mixing angle sin 2 \theta < 10^{-2} could generate a large lepton asymmetry in the Early Universe. The final order of magnitude of the lepton asymmetry \eta is mainly determined by its growth in the last stage of evolution, the so called power-law regime. There exist two contradictory results in the literature, \eta \propto T^{-1} and \eta \propto T^{-4}, where T is the background medium temperature. In the first case, the lepton asymmetry does not exceed values of 10^{-4} for |\delta m^2| < 1 eV^2, while in the second case it can become larger than 10^{-1}. In this work we analytically investigate the case \eta \propto T^{-1}, using a new approach to solve the kinetic equations. We find that the power-law solution \eta \propto T^{-1} is not self-consistent. Instead, we find the power law \eta \propto T^{-11/3} to be a good approximation, which leads to a large final asymmetry.
Buras Robert
Semikoz Dmitri V.
No associations
LandOfFree
Lepton asymmetry creation in the Early Universe does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Lepton asymmetry creation in the Early Universe, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Lepton asymmetry creation in the Early Universe will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-346971