TY  - EJOUR
AU  - Domcke, Valerie Fiona
AU  - Drewes, Marco
AU  - Hufnagel, Marco
AU  - Lucente, Michele
TI  - MeV-scale Seesaw and Leptogenesis
IS  - arXiv:2009.11678
M1  - PUBDB-2020-03620
M1  - arXiv:2009.11678
M1  - CERN-TH-2020-158
M1  - DESY-20-159
PY  - 2020
AB  - We study the type-I seesaw model with three right-handed neutrinos and Majorana masses below the pion mass. In this mass range, the model parameter space is not only strongly constrained by the requirement to explain the light neutrino masses, but also by experimental searches and cosmological considerations. In the existing literature, three disjoint regions of potentially viable parameter space have been identified. In one of them, all heavy neutrinos decay shortly before big bang nucleosynthesis. In the other two regions, one of the heavy neutrinos either decays between BBN and the CMB decoupling or is quasi-stable. We show that previously unaccounted constraints from photodisintegration of nuclei practically rule out all relevant decays that happen between BBN and the CMB decoupling. Quite remarkably, if all heavy neutrinos decay before BBN, the baryon asymmetry of the universe can be quite generically explained by low-scale leptogenesis, i.e. without further tuning in addition to what is needed to avoid experimental and cosmological constraints. This motivates searches for heavy neutrinos in pion decay experiments.
KW  - nucleosynthesis: big bang (autogen)
KW  - neutrino: heavy: decay (autogen)
KW  - cosmic background radiation: decoupling (autogen)
KW  - neutrino: heavy (autogen)
KW  - neutrino: decay (autogen)
KW  - neutrino: mass (autogen)
KW  - neutrino: heavy: search for (autogen)
KW  - neutrino: right-handed (autogen)
KW  - pi: decay (autogen)
KW  - pi: mass (autogen)
KW  - mass: Majorana (autogen)
KW  - baryon: asymmetry (autogen)
KW  - leptogenesis (autogen)
KW  - seesaw model (autogen)
KW  - nucleus (autogen)
LB  - PUB:(DE-HGF)25
DO  - DOI:10.3204/PUBDB-2020-03620
UR  - https://bib-pubdb1.desy.de/record/449168
ER  -