Flavor effects in thermal leptogenesis

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Flavor effects in thermal leptogenesis
JIGSAW 2007 Neutrinos in Physics, Astrophysics
and Cosmology Mumbai, India, February 12-23,
2007

• Steve Blanchet
• Max-Planck-Institut für Physik, Munich

SB, P. Di Bari, hep-ph/0607330 SB, P. Di Bari, G.
G. Raffelt, hep-ph/0611337
Based on
February 16, 2007
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Posters content

• Review of the old unflavored leptogenesis and
  its main implications

• Lower bound on the mass of the lightest heavy
  neutrino

• Upper bound on the absolute neutrino mass scale

• No direct connection between low-energy CP
  violation and leptogenesis

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Posters content

• Basics of the new flavored leptogenesis

• Fast charged lepton interactions may break the
  coherence of the produced lepton states.

• Rough condition for flavor effects

• New Boltzmann equations result.

• Implications of the flavored equations

• The lower bound still holds

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Posters content

• Leptogenesis only from non-zero phases in the
  PMNS matrix is possible.

• Flavor effects can lead to very large differences
  in the resulting final baryon asymmetry compared
  to unflavored leptogenesis, especially when a
  degenerate light neutrino spectrum is considered.

• The stringent neutrino mass bound is evaded if
  one believes classical Boltzmann equations for
  the whole range of parameters.

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Posters content

• But only a correct density matrix equation should
  be able to answer the question of the neutrino
  bound