Higgs Doublet Decay as the Origin of the Baryon Asymmetry.
Phys Rev Lett
; 117(9): 091801, 2016 Aug 26.
Article
en En
| MEDLINE
| ID: mdl-27610845
ABSTRACT
We consider a question that curiously had not been properly considered thus far in the standard seesaw model, what is the minimum value the mass of a right-handed (RH) neutrino must have for allowing successful leptogenesis via CP-violating decays? Answering this question requires us to take into account a number of thermal effects. We show that, for low RH neutrino masses, and thanks to these effects, leptogenesis turns out to proceed efficiently from the decay of the standard model scalar doublet components into a RH neutrino and a lepton. Such decays produce the asymmetry at low temperatures, slightly before sphaleron decoupling. If the RH neutrino has thermalized prior to producing the asymmetry, this mechanism turns out to lead to the bound m_{N}>2 GeV. If, instead, the RH neutrinos have not thermalized, leptogenesis from these decays is enhanced further and can be easily successful, even at lower scales. This Higgs-decay leptogenesis new mechanism works without requiring an interplay of flavor effects and/or cancellations of large Yukawa couplings in the neutrino mass matrix. Last but not least, such a scenario turns out to be testable, from direct production of the RH neutrino(s).
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1
Colección:
01-internacional
Banco de datos:
MEDLINE
Idioma:
En
Revista:
Phys Rev Lett
Año:
2016
Tipo del documento:
Article
País de afiliación:
Bélgica