Post-sphaleron conversion between baryon and lepton numbers

Abstract: The conversion between baryon and lepton numbers has a significant impact on the mechanisms for dynamically generating the matter-antimatter asymmetry in the present universe. Under the traditional wisdom, such conversion originates from the so-called electroweak sphaleron processes. In this work we find that in association with a proper scalar and the other TeV new physics, the baryon-lepton conversion can still keep efficient after the electroweak sphalerons are no longer active. Moreover this scenario can provide a solution to the puzzle of neutron lifetime and predict some decay modes of multi-nucleons to multi-leptons.