TY  - JOUR
AU  - Barenboim, G.
AU  - Park, W. I.
PY  - 2017
DA  - 2017//
TI  - A full picture of large lepton number asymmetries of the Universe
T2  - J. Cosmol. Astropart. Phys.
JO  - Journal of Cosmology and Astroparticle Physics
SP  - 048
EP  - 10pp
VL  - 04
IS  - 4
PB  - Iop Publishing Ltd
KW  - cosmological neutrinos
KW  - cosmology of theories beyond the SM
KW  - leptogenesis
KW  - physics of the early universe
AB  - A large lepton number asymmetry of O(0.1-1) at present Universe might not only be allowed but also necessary for consistency among cosmological data. We show that, if a sizeable lepton number asymmetry were produced before the electroweak phase transition, the requirement for not producing too much baryon number asymmetry through sphalerons processes, forces the high scale lepton number asymmetry to be larger than about 30. Therefore a mild entropy release causing O(10-100) suppression of pre-existing particle density should take place, when the background temperature of the Universe is around T = O(10(-2) -10(2)) GeV for a large but experimentally consistent asymmetry to be present today. We also show that such a mild entropy production can be obtained by the late-time decays of the saxion, constraining the parameters of the Peccei-Quinn sector such as the mass and the vacuum expectation value of the saxion field to be m(phi) greater than or similar to O(10) TeV and phi(0) greater than or similar to O(10(14)) GeV, respectively.
SN  - 1475-7516
UR  - http://arxiv.org/abs/1703.08258
UR  - https://doi.org/10.1088/1475-7516/2017/04/048
DO  - 10.1088/1475-7516/2017/04/048
LA  - English
N1  - WOS:000401806200048
ID  - Barenboim+Park2017
ER  -