Figure 1

The red line shows the maximal mixing $|{\mathrm{\Theta }}_{\mu 2}{|}^2$ we found consistent with baryogenesis, i.e. below the line there exist parameter choices for which the observed BAU can be generated. The scatter is a result of the Monte Carlo method and not physical. It indicates that we have not found the global maxima, but the density of valid points decreases rapidly for larger $|{\mathrm{\Theta }}_{\mu 2}{|}^2$. The gray area represents bounds from the past experiments PS191 [85], NuTeV [86] (both reanalyzed in [87]), NA3 [88], CHARMII [89] and DELPHI [90] (as given in [91]). They are stronger than those from violation of lepton universality [92, 93, 94, 95], see [2, 91] for a discussion of other experimental constraints. The blue lines indicate the current bounds from LHCb [96] (dotted) and Belle [97] (dashed), which will improve in the future.