Nonthermal leptogenesis with almost degenerate superheavy neutrinos

Allahverdi, Rouzbeh and Mazumdar, Anupam (2003) Nonthermal leptogenesis with almost degenerate superheavy neutrinos. Physical Review D, 67 (2). ISSN 1550-7998

[thumbnail of PhysRevD.67.023509.pdf]
Preview
PDF
PhysRevD.67.023509.pdf - Published Version

Download (99kB)

Abstract

We present a model with minimal assumptions for non-thermal leptogenesis with almost degenerate superheavy right-handed neutrinos in a supersymmetric set up. In this scenario a gauge singlet inflaton is directly coupled to the right-handed (s)neutrinos with a mass heavier than the inflaton mass. This helps avoiding potential problems which can naturally arise otherwise. The inflaton decay to the Standard Model leptons and Higgs, via off-shell right-handed (s)neutrinos, reheats the Universe. The same channel is also responsible for generating the lepton asymmetry, thus requiring no stage of preheating in order to excite superheavy (s)neutrinos. The suppressed decay rate of the inflaton naturally leads to a sufficiently low reheat temperature, which in addition, prevents any wash out of the yielded asymmetry. We will particularly elaborate on important differences from leptogenesis with on-shell (s)neutrinos. It is shown that for nearly degenerate neutrinos a successful leptogenesis can be accommodated for a variety of inflationary models with a rather wide ranging inflationary scale.

Item Type:
Journal Article
Journal or Publication Title:
Physical Review D
Additional Information:
© 2003 The American Physical Society 10 revtex pages, 2 figure (uses axodraw). The derivation of the asymmetry parameter for the general case and one figure added. Final version to appear in Phys. Rev. D
ID Code:
63437
Deposited By:
Deposited On:
03 May 2013 09:21
Refereed?:
Yes
Published?:
Published
Last Modified:
15 Sep 2023 00:07