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Title: Neutrino helicity asymmetries in leptogenesis

Abstract

It is pointed out that the heavy singlet neutrinos characteristic of leptogenesis develop asymmetries in the abundances of the two helicity states as a result of the same mechanism that generates asymmetries in the standard lepton sector. Neutrinos and standard leptons interchange asymmetries in collisions with each other. It is shown that an appropriate quantum number, B-L{sup '}, combining baryon, lepton and neutrino asymmetries, is not violated as fast as the standard B-L. This suppresses the washout effects relevant for the derivation of the final baryon asymmetry. One presents detailed calculations for the period of neutrino thermal production in the framework of the singlet seesaw mechanism.

Authors:
;  [1]
  1. Universidade de Lisboa, Faculdade de Ciencias, Centro de Fisica Nuclear da Universidade de Lisboa, Avenida Prof. Gama Pinto 2, 1649-003 Lisbon (Portugal)
Publication Date:
OSTI Identifier:
20709408
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 71; Journal Issue: 9; Other Information: DOI: 10.1103/PhysRevD.71.096001; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ABUNDANCE; ASYMMETRY; BARYONS; HELICITY; NEUTRINO REACTIONS; NEUTRINOS; PARTICLE INTERACTIONS; PARTICLE PRODUCTION; SYMMETRY

Citation Formats

Bento, Luis, and Santos, Francisco C. Neutrino helicity asymmetries in leptogenesis. United States: N. p., 2005. Web. doi:10.1103/PhysRevD.71.096001.
Bento, Luis, & Santos, Francisco C. Neutrino helicity asymmetries in leptogenesis. United States. doi:10.1103/PhysRevD.71.096001.
Bento, Luis, and Santos, Francisco C. 2005. "Neutrino helicity asymmetries in leptogenesis". United States. doi:10.1103/PhysRevD.71.096001.
@article{osti_20709408,
title = {Neutrino helicity asymmetries in leptogenesis},
author = {Bento, Luis and Santos, Francisco C.},
abstractNote = {It is pointed out that the heavy singlet neutrinos characteristic of leptogenesis develop asymmetries in the abundances of the two helicity states as a result of the same mechanism that generates asymmetries in the standard lepton sector. Neutrinos and standard leptons interchange asymmetries in collisions with each other. It is shown that an appropriate quantum number, B-L{sup '}, combining baryon, lepton and neutrino asymmetries, is not violated as fast as the standard B-L. This suppresses the washout effects relevant for the derivation of the final baryon asymmetry. One presents detailed calculations for the period of neutrino thermal production in the framework of the singlet seesaw mechanism.},
doi = {10.1103/PhysRevD.71.096001},
journal = {Physical Review. D, Particles Fields},
number = 9,
volume = 71,
place = {United States},
year = 2005,
month = 5
}
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