Science-advisor
REGISTER info/FAQ
Login
username
password
     
forgot password?
register here
 
Research articles
  search articles
  reviews guidelines
  reviews
  articles index
My Pages
my alerts
  my messages
  my reviews
  my favorites
 
 
Stat
Members: 3643
Articles: 2'488'730
Articles rated: 2609

29 March 2024
 
  » arxiv » hep-ph/0305322

 Article overview


Probing the seesaw mechanism with neutrino data and leptogenesis
Evgeny Kh. Akhmedov ; Michele Frigerio ; Alexei Yu. Smirnov ;
Date 29 May 2003
Journal JHEP 0309 (2003) 021
Subject hep-ph astro-ph hep-ex
AffiliationICTP, Trieste), Michele Frigerio (INFN & SISSA, Trieste), Alexei Yu. Smirnov (ICTP, Trieste & INR, Moscow
AbstractIn the framework of the seesaw mechanism with three heavy right-handed Majorana neutrinos and no Higgs triplets we carry out a systematic study of the structure of the right-handed neutrino sector. Using the current low-energy neutrino data as an input and assuming hierarchical Dirac-type neutrino masses $m_{Di}$, we calculate the masses $M_i$ and the mixing of the heavy neutrinos. We confront the inferred properties of these neutrinos with the constraints coming from the requirement of a successful baryogenesis via leptogenesis. In the generic case the masses of the right-handed neutrinos are highly hierarchical: $M_i propto m_{Di}^2$; the lightest mass is $M_1 approx 10^3 - 10^6$ GeV and the generated baryon-to-photon ratio $eta_Blesssim 10^{-14}$ is much smaller than the observed value. We find the special cases which correspond to the level crossing points, with maximal mixing between two quasi-degenerate right-handed neutrinos. Two level crossing conditions are obtained: ${m}_{ee}approx 0$ (1-2 crossing) and $d_{12}approx 0$ (2-3 crossing), where ${m}_{ee}$ and $d_{12}$ are respectively the 11-entry and the 12-subdeterminant of the light neutrino mass matrix in the basis where the neutrino Yukawa couplings are diagonal. We show that sufficient lepton asymmetry can be produced only in the 1-2 crossing where $M_1 approx M_2 approx 10^{8}$ GeV, $M_3 approx 10^{14}$ GeV and $(M_2 - M_1)/ M_2 lesssim 10^{-5}$.
Source arXiv, hep-ph/0305322
Services Forum | Review | PDF | Favorites   
 
Visitor rating: did you like this article? no 1   2   3   4   5   yes

No review found.
 Did you like this article?

This article or document is ...
important:
of broad interest:
readable:
new:
correct:
Global appreciation:

  Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.

browser claudebot






ScienXe.org
» my Online CV
» Free


News, job offers and information for researchers and scientists:
home  |  contact  |  terms of use  |  sitemap
Copyright © 2005-2024 - Scimetrica