Baryogenesis by B - L generation due to superheavy particle decay

We have shown that the $B-L$ generation due to the decay of the thermally produced superheavy fields can explain the Baryon assymmetry in the universe if the superheavy fields are heavier than $10^{13-14}$ GeV. Note that although the superheavy fields have non-vanishing charges under the standard model gauge interactions, the thermally prduced baryon asymmetry is sizable. The $B-L$ violating effective operators induced by integrating the superheavy fields have dimension 7, while the operator in the famous leptogenesis has dimension 5. Therefore, the constraints from the nucleon stability can be easily satisfied.